Braided structures of complex geometry

ABSTRACT

A braided sleeve with complex geometry, including changes to the geometry along the braided sleeve&#39;s longitudinal axis are described. In particular, along a first portion of the braided sleeve&#39;s longitudinal axis, multiple tows are intertwined with each other. Along a second portion, one of tows is removed from being intertwined with the other tows and is relocated to an interior or an exterior of the braided sleeve. A third portion includes the removed tow being intertwined with the plurality of tows again. In this manner, the braided sleeve may provide coverage of preforms with varying diameters along the longitudinal axis of the preforms.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation of U.S. patent applicationSer. No. 16/259,236, filed on Jan. 28, 2019, which is a continuation ofU.S. patent application Ser. No. 15/811,435, filed on Nov. 13, 2017, nowabandoned, which is a continuation of U.S. patent application Ser. No.15/089,548, filed on Apr. 2, 2016, now U.S. Pat. No. 9,816,210, whichclaims priority to and the benefit of U.S. Provisional Application No.62/142,603 filed on Apr. 3, 2015, all of which is incorporated byreference herein in their entirety.

TECHNICAL FIELD

The present subject matter relates to allantoidal braided structures aswell as braided structures with complex geometry and a method for theformation of the braided structures.

BACKGROUND

Conventional braiding machines may be comprised of a plurality of towcarrier devices dispersed around a braiding machine track. Braidedproducts formed by conventional braiding machines may be comprised of atwo over, two under (2×2) braid architecture in which two clockwisetraveling tow carrier devices may pass over two counterclockwisetraveling tow carrier devices and under two counterclockwise travelingtow carrier devices in a repeating pattern. Tow carrier devices maytravel circumferentially as well as radially inwards and outwards aroundthe braiding machine track to promote the intertwining of tows to formthe braided structure.

Braided products comprised of 2×2 braid architectures may be overbraidedonto preforms of complex geometry in which the largest cross-sectionalportion of the preform may be larger than that of the smallestcross-sectional portion of the preform. One example of a preform ofcomplex geometry may be a classic Coca-Cola® bottle; wherein a straw issymmetrically affixed in the center of the opening. The straw may beanalogized to the center of a braiding machine and the exterior surfaceof the bottle may be analogized to a preform having a complex geometryonto which braid may be formed. The formation of the braided structuremay be initiated at the top of the coke bottle. The braiding machinetrack may be located near the base of the bottle, or the largestcross-sectional portion of the coke bottle. Tows affixed to tow carrierdevices traveling around the braiding machine track intertwine to form abraided structure around the outer surface of the coke bottle which maybe analogous to a sleeve covering the surface of the coke bottle. Thecoke bottle may be vertically advanced as the braiding structure formson the outer surface of the coke bottle. The cross section of the cokebottle transverse to the longitudinal axis represented by the straw maybe transitory and represented as a series of circular shapes having aseries of varying diameters. The diameter of the opening of the cokebottle may comprise the smallest cross-sectional diameter, while thebase may comprise the largest cross-sectional diameter. In one example,the ratio of cross-sectional diameter of the largest portion of apreform of complex geometry to the smallest portion of the preform ofcomplex geometry may be 5 to 1, 3 to 1, 10 to 1 and other variations,such as 5 to 2 and 3 to 2 etc. In additional examples, if the largestcross-sectional portion of the preform were to exceed three times thatof the smallest cross-sectional portion of the preform, bunching orwrinkling of the braided product may occur. A higher ratio of thelargest to the smallest cross-sectional diameter of the preform mayexacerbate these structural imperfections.

Conventional 2×2 braided products may experience low compaction of towswithin the braided structure as well as high compaction of tows withinthe braided structure as a result of the complex geometry of the preformon which the braided product may be overbraided. A low compaction areamay be described as an area in which the tows within the braidedstructure may be spaced apart while a high compaction area may bedescribed as an area in which tows may be touching, overlapping orstacked on top of another. In a case in which the largest portion of thepreform may exceed three times that of the smallest portion of thepreform, bunching or wrinkling of the braided product may occur.Bunching or wrinkling may occur when tows within the braided structuremay not be compacted, in a high compaction situation, any closertogether. This may place stress on the braided structure and may causethe braided structure to bunch or wrinkle to allow further compaction ofthe braided structure to take place. This distortion of the braidedstructure is undesirable.

The creation of braided structures with reduced distortion whenoverbraided onto preforms of complex geometry, in which the ratio of thelargest cross-sectional diameter of the braided product to the smallestcross-sectional diameter of the braided product may exceed a generallythree to one ratio, is desired.

Braided structures created using traditional maypole style braidingmachines may conventionally be produced in a tubular form. Braidedtubular sleeves may be overbraided onto preforms with complexcross-sectional geometries, and may conform to the shape of thesepreforms. However, this may lead to disruption in the braided structure;inducing areas of high and low tension and resulting in variation ofbias angle across the preform. This may be especially evident whenpreforms of varying large and small cross-sectional geometries along thelongitudinal axis may be overbraided with braided sleeve products. Inthese products, areas of large cross-sectional geometries may experiencehigh tension and distorted braid geometry, or high bias angles, whilesmall cross-sectional geometries may experience very low tension, lowbias angles and may not conform well to smaller cross-sectionalgeometries especially in cases in which the difference between the largeand small cross-sectional geometries may be significant, including 5:1,8:1 or 10:1 ratios.

A method for the creation of a braided product which may maintain thesame tension over all sections of a preform with varying cross-sectionalgeometry is desired.

Further, tubular braided products overbraided onto preforms such asflexible tubing may tend to bunch or kink at bending locations. In acontinuing discussion of a Coca-Cola® bottle as a preform of complexgeometry, two coke bottles may be affixed such that each top of eachcoke bottle is coincident and concentric. The location at which the twocoke bottles are affixed to one another may be defined as the bendinglocation. At this location, the smallest diameter cross-sectionalportions of the coke bottles are in contact and when affixed maycomprise a continuous section of small cross-sectional diameter. Withincommercial braided products, it is desired to orient the two affixedcoke bottles parallel to one another. To achieve this, the two affixedcoke bottle tops must be curved in relation to the axis of each bottledefined by the straw. As a result, it may be envisioned that as theaffixed coke bottle tops are curved, one portion of each top must becomestretched, while another portion must compress to form a “U” shape suchthat the two coke bottles may become parallel to one another. Thedistortions resulting from such an arrangement is undesirable incommercial braided as an area of high material density, wrinkling anddistortion in the braided product may be created below the bendingpoint, or the smallest portion of the “U” shape or bending radius whilean area of high tension and high bias angle may be created within thebraided product over the bending point, or the largest portion of the“U” shape or bend radius. It is desired to eliminate these distortionsat bending locations in braided products.

In addition, the braid architecture as well as the number of tow carrierdevices present in conventional braiding machines may not be easily orefficiently altered during the braiding process. Additional flexibilityin the number of tow carrier devices a braiding machine may comprise ata single point in time is desirable to maximize the diversity ofproducts which may be produced on a single braiding machine.

SUMMARY

The present subject matter relates to allantoidal braided structures aswell as braided structures with complex geometry and a method for theformation of the braided structures.

The present subject matter relates in particular to embodiments of abraiding machine which may be comprised of a plurality of tow carrierdevices dispersed across a braiding machine surface comprising a track,or guide, on which tow carrier devices may travel circumferentiallyaround the braiding machine as well as radially inwards and outwardsfrom the braiding machine center to allow for the intertwining of towmaterials. In addition, the present subject matter relates to theformation of a high compaction braided structures which, in oneembodiment, may be comprised of an N×N braid architecture, where N maybe any number greater than two.

The present subject matter relates to a braiding machine comprised oftow carrier transfer devices which, in an embodiment, may be horn diskscomprised of a number of radial slots, 2N to allow for the acceptance ofN, S traveling tow carrier devices and N, Z traveling tow carrierdevices in each horn disk or tow carrier transfer device.

Additionally, the present subject matter relates to a braided structurewith longitudinally varying architecture. The braiding machine of thepresent subject matter may generally be comprised of a plurality of towcarrier devices dispersed around a braiding machine track. Further, thebraiding machine may comprise an outer braiding machine track on whichbraiding occurs and an inner ring, or a sequester ring, comprised ofsequester disks which may allow for the addition and removal of towcarrier devices from the outer braiding machine track.

The braided structure of embodiments of the present subject matter maybe comprised of a pattern of varying braid architecture in which braidarchitectures comprised of high numbers of tows crossing over and undereach other, for example 5×5 braid architecture, may correspond withlarger cross-sectional dimensions of the braided product. Conversely,braid architectures comprised of low numbers of tows crossing over andunder each other, for example 1×1 braid architectures, may correspondwith small cross-sectional dimensions of the braided product.

In addition, the braided product may be comprised of sections in whichthe braid architecture may transition from a higher number of towscrossing over and under each other, for example a 5×5 braidarchitecture, to a lower number of tows crossing over and under eachother, for example 1×1 braid architecture.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates a generally allantoidal preform;

FIG. 2 illustrates the compaction of tows in a low compaction situation;

FIG. 3 illustrates the compaction of tows in a moderate high compactionsituation;

FIG. 4 illustrates the compaction of tows in a high compactionsituation;

FIG. 5 illustrates the position of tow carrier devices and thecomponents of which they are comprised far from and close to the centerof the braiding machine;

FIG. 6 illustrates a tow carrier device comprised of multiple dropweight and bottom eye assemblies;

FIGS. 7A and 7B describe the motion of tow carrier devices and thecomponents of which they are comprised during the braiding process;

FIG. 8 describes the process by which a high compaction braidedstructure may be overbraided onto a preform of complex geometry;

FIG. 9 illustrates a high compaction braided product overbraided over agenerally allantoidal preform;

FIG. 10 illustrates a high compaction braided product overbraided onto agenerally bellows shaped preform;

FIG. 11 illustrates a high compaction braided product overbraided onto agenerally flabelliform preform;

FIG. 12 is illustrative of a partial braiding machine ring and sequesterring of embodiments of the braiding machine herein;

FIG. 13 illustrates a plurality of sequester disks and horn disks;

FIG. 14 illustrates a cross-sectional view of the braiding machine ofthe present subject matter;

FIG. 15 is illustrative of a simplification of a braiding machine;

FIG. 16 illustrates a braiding machine for the manufacture of a braidedstructure with longitudinally varying architecture in which a pluralityof tow carrier devices have been sequestered;

FIG. 17 illustrates a braiding machine for the manufacture of a braidedstructure with longitudinally varying architecture in which no towcarrier devices have been sequestered;

FIG. 18 illustrates the braided structure of the present subject mattercomprised of a longitudinally varying braid architecture;

FIG. 18A illustrates the braided structure of the present subject mattercomprised of a longitudinally varying architecture which comprises atransitory bias angle within the 5×5 braid architecture;

FIG. 19 illustrates a 5×5 braid architecture overbraided over a firstsection of a preform comprised of large cross-sectional geometry;

FIG. 19A illustrates a 5×5 braid architecture comprising a transitorybias angle overbraided over a first section of a preform comprised oflarge cross-sectional geometry

FIG. 20 illustrates a 5×5 braid architecture overbraided over a firstsection of a preform comprised of large cross-sectional geometry and a4×4 braid architecture overbraided over a second section of the preform;

FIG. 21 illustrates a 5×5 braid architecture overbraided over a firstsection of a preform comprised of large cross-sectional geometry, a 4×4braid architecture overbraided over a second section and a 3×3 braidarchitecture overbraided over a third section of the preform;

FIG. 22 illustrates a 5×5 braid architecture overbraided over a firstsection of a preform comprised of large cross-sectional geometry, a 4×4braid architecture overbraided over a second section, a 3×3 braidarchitecture overbraided over a third section of the preform, and a 2×2braid architecture overbraided over a fourth section of the preform;

FIG. 23A illustrates a cross-sectional view of a braided structure withlongitudinally varying architecture while FIG. 23B illustrates a crosssection of the preform and braided structure of the present subjectmatter depicting removal and reintroduction points of a tow;

FIG. 24 illustrates the braided structure with longitudinally varyingarchitecture illustrating the sequestration of tows in which tows may bewrapped around a specific section of the allantoidal preform;

FIG. 25 illustrates the braided structure with longitudinally varyingarchitecture illustrating the removal and introduction of tows withinthe braided structure;

FIG. 26 illustrates a plurality of allantoidal preforms overbraided withthe braided structure with longitudinally varying architecture in anon-collinear arrangement.

DETAILED DESCRIPTION

The present subject matter relates to allantoidal braided structures aswell as braided structures with complex geometry and a method for theformation of the braided structures described herein.

Braided structures are used extensively in the manufacture of compositeparts as reinforcements materials embedded in a resin matrix. It is alsoknown to use braided structures as distinct components within anassembly of parts, for instance, as a blade-out containment component ina jet engine component. Braided structures are often preferred overother types of structures, such as woven structures, because tows ofmaterial within the structure can be oriented along non-perpendiculardirections and the structures can either conform to a surface uponapplication or be manufactured in to conform to a specific surface.

As used herein, a “braided structure” is a product comprised of three ormore strands of material (tows) such that each tow is joined with othertows in a repeating intertwined pattern. Two-dimensional braidedmaterials are those wherein the repeating pattern is largelycharacterized by two or more principal directions in a plane, typicallythe longitudinal direction of the braided structure, commonly called thelongitudinal axis or the, axial direction and one or more obliquedirections, commonly called bias directions, each at a predeterminedangle to the longitudinal axis or direction.

The term longitudinal axis as used in the specification herein refers toan axis generally perpendicular to the braiding machine track alongwhich a braided structure is formed. This longitudinal axis isadditionally described in reference to braided structures in which biastow materials are oriented in angular positions in reference to thelongitudinal axis of the braided structure, or along the axis in whichthe braided structure was formed. Examples of bias directions forvarious braiding architectures with respect to the longitudinal axisinclude 45° and 60° angular positions. Three-dimensional braidedstructures are those wherein additional principal directions, generallymutually perpendicular to the longitudinal and oblique directions, arerequired to completely define the structure and the patterns thereof.For simplicity of description, these additional directions aregenerically referred to as radial directions, whether the structure isgenerally tubular in form, laid out as a flattened tubular form or in afabric, or generally planar form.

Two-dimensional braided structures may be manufactured as generallycylindrical materials, commonly called sleeves, with the axial directioncorresponding to the longitudinal axis of the cylinder and the biasdirections oblique to the longitudinal axis. Braided structuresmanufactured in cylindrical form may then be laid-flat to form atwo-dimensional fabric comprised of two layers joined along thelongitudinal edges. The edges may be removed to form two separate anddistinct layers. One edge may be removed and the cylindrical structurelaid-flat to form a singly-slit single layer structure. Two edges may beremoved to form a double-slit two layer structure. Two-dimensionalbraided structures may further be manufactured in a single layer flatform, commonly called a tape.

In this disclosure reference to braided structure generally impliestwo-dimensional forms but does not exclude three-dimensional forms.

In this disclosure reference to braided fabric is generally directed totwo-dimensional fabric forms but one skilled in the art recognizes thatthree-dimensional braided materials may be used in particularembodiments of the present invention as desired to satisfy requirementsof particular applications.

Common terms used to describe braided structures are based on aCartesian system of directions and rotations as applied to a planesurface considered to be formed from cylindrical surface after it isslit in the direction of the longitudinal axis and the cylindricalsurface rolled out into a plane.

The longitudinal axis of braided structures is often used as a referencedirection when describing the orientations of sets of tows in thebraided structure. Directions oblique to the longitudinal axis are oftenreferred to as bias directions. Oblique directions oriented at anglesclockwise to the longitudinal axis are generally referred to as positivebias directions and those oriented at angles counterclockwise to thelongitudinal axis are generally referred to as negative bias directions.

Biaxial braided structures have two sets of tows, one oriented along apositive bias direction and the other along a negative bias direction. Atypical shorthand description of the orientations of the two sets withina biaxial braided structure is comprised of a positive and a negativenumber each numerating the bias angle for a set of tows. For example, abiaxial braided structure called Bimax, manufactured by A&P Technology,Inc., is designated as a +45°/−45° braid.

An inherent feature of biaxial braided structures is that the towscomprising the braided structure can move relative to one another andallow the braided structure to conform to a range of surfaces withoutcompromising the braided structure or the tows. After conformation to aspecific surface the general relative orientation of tows within setsand set to set is maintained and may be best understood by consideringthe Cartesian system to have been mapped onto the surface.

Triaxial braided structures may be manufactured to conform to a specificsurface at the time of manufacture by overbraiding onto a specificsurface so that the locking action of the axial tows occurs as thebraided structure is laid on the surface and the geometry of the braidedstructure assumes and retains its as-manufactured configuration.

The addition of axial tows restricts relative motion of tows therebygenerally locking the structure in the as-manufactured geometry.Triaxial braided structures are generally used in sheet or tubular formor are manufactured to conform to a specific surface at the time ofmanufacture.

Triaxial braided structures have three sets of tows. Two sets areoriented as described for biaxial structures. The third set of tows isoriented along the longitudinal axis and intertwined with the first andsecond set of tows. A typical shorthand description for a triaxial braidstructure includes the angular orientation of each tow set relative tothe longitudinal axis and the longitudinal axis itself to better conveythat the braided structure is triaxial. For example, a triaxial braidedstructure marketed as Qiso, manufactured by A&P Technology, isdesignated as a +60°/0°/−60° braid structure.

The terms “strand”, “tow”, “yarn”, “yarn bundle”, “fiber” and “fiberbundle” are generally meant to describe a primary intertwined componentof the braided structure, laid in each of the principal directions. Thetow itself may be comprised of multiple components (e.g., individualfilaments) that run together in a principal direction. A tow cancomprise monofilament arrangements, multiple filament arrangements or becomprised of staple or spun material. Tow material can have a variety ofcross-sectional shapes, including but not limited to, circular,ellipsoidal, triangular and flat tape shapes, as well as other variantsthereof. Tow material may be subject to intermediate or pre-processingprior to braiding operations. Examples of intermediate or pre-processingmay include, but are not limited to, twisting, braiding small numbers offilaments into braided tow materials, pre-impregnation with resins andspecialty coating to facilitate braiding and/or subsequent processing. Atow can comprise any combination of these materials and material forms.Any one tow may comprise one or more filament or staple materials. Asnon-limiting examples, a tow may be comprised of carbon materials,basalt, glass materials, thermoplastic polymeric materials, thermosetpolymeric materials, a combination of carbon and polymeric materials ora combination of polymeric and glass materials, or some combinationthereof. Tows that lay in one of the bias directions of the fabric arecommonly called bias tows. Tows that lay along the longitudinal axis ofthe fabric are commonly called axial tows.

As used herein, the term braid architecture may be defined as thepattern in which tow materials oriented in bias directions may beintertwined to form a braided structure in which an integer, N, ofclockwise oriented tows may pass over and under N counterclockwiseoriented tows and in which an integer, N, of counterclockwise orientedtows may pass under and over N clockwise traveling tows. The term braidarchitecture may also describe, in additional manners, the types of towmaterials which comprise a braided structure including in non-limitingexample braided structures comprised of axial and bias tows for theformation of a triaxial braided structure, or braided products comprisedonly of bias tows for the formation of a biaxial braided structure, orbraided structures comprised of sections of biaxial and triaxialsections, or hybrid braided structures. As used herein, biaxial braiddescribes braided structures comprised of bias tows. Triaxial braid iscomprised of bias and axial tows. Hybrid braided structure are comprisedof contiguous tow materials comprising adjacent regions of biaxial andtriaxial braided structures.

The term contiguous as described herein refers to undisrupted lengths ofa tow material within a braided structure. Disruption in the length of atow may be described as the presence of splices, stitching, tying orother methods of cutting and reaffixing portions of tow material to oneanother.

In the art several terms in common use describe the most common braidarchitectures. For example, in regular or plain braid architecture eachbias tow is intertwined into the structure such that it passes over twobias tows in the opposing bias direction and under two bias tows in theopposing bias direction in a repeated pattern. The numerical designation2×2, typically read as “two-over, two-under”, may be used to define thispattern. Similarly, Hercules braid architecture is a 3×3 architecturewherein each bias tow passes over three bias tows in the opposing biasdirection then under three bias tows in the opposing bias direction in arepeated pattern. Further, diamond braid architecture is 1×1architecture.

As used herein, a braiding machine is an apparatus for manufacture ofbraided structures. Said machine may be specific to a particular braidarchitecture or family of related braid architectures or general in thatit can produce multiple braid architectures. Examples of braidingmachines include maypole braiding machines or 3D braiding machines.

Biaxial and triaxial two-dimensional braids are commonly made on maypolebraiding machines. A maypole braiding machine is generally comprised ofa flat ring assembly on which tow carrier devices are deployed. The towcarrier devices are transported along the circumferential direction ofthe flat ring and caused to move in and out along the radial direction.One group of tow carrier devices, generally half the number of total towcarriers deployed in the machine, moves in the counterclockwise, or S,circumferential direction and another group of tow carrier devices movesin the clockwise, or Z, circumferential direction. For descriptionpurposes, the tow carrier devices moving in the S circumferentialdirection are called the S carriers and those moving in the Zcircumferential direction are called the Z carriers. The combination ofcircumferential and inner and outer radial motion affects intertwiningof the S and Z carriers. For a regular or plain 2×2 braid, the S and Zcarriers move in the circumferential and radial directions so that thetow paid out by each S carrier passes over two Z carrier tows and undertwo Z carrier tows in a repeated pattern and vice versa for Z and Scarriers.

The present subject matter relates in particular to embodiments of abraiding machine which may be comprised of a plurality of tow carrierdevices dispersed across a braiding machine surface comprising a track,or guide, on which tow carrier devices may travel circumferentiallyaround the braiding machine as well as radially inwards and outwardsfrom the braiding machine center to allow for intertwining of towmaterials. In addition, the present subject matter relates toallantoidal braided structures as well as braided structures withcomplex geometry and a method for the formation of the braidedstructures.

An embodiment of the braided structure of the present subject matterrelates to the formation of a high compaction braided structure which,in embodiments herein, may be comprised of a ten over and ten under(10×10) braid architecture in which ten S traveling tow carrier devicespass under ten Z traveling tow carrier devices and over ten Z towcarrier devices in a repeating pattern, and ten Z traveling tow carrierdevices pass over ten S traveling tow carrier devices and under ten Straveling tow carrier devices in a repeating pattern.

The high compaction braided structure of the present subject matter mayhave particular utility for the formation of braided products comprisingcomplex geometry including, but not limited to allantoidal 100 a braidedproducts and braided products which must undergo physical shape changesas a function of application. One example of an allantoidal braidedproduct is shown in FIG. 1 as structure 100 a.

Allantoidal shaped braided products 100 a may be described as braidedproducts which may be comprised of several sections of invariablecross-sectional diameters, 101 and 103, and several sections oftransitory cross-sectional diameters, 102, between sections ofinvariable cross-sectional diameters, 101 and 103. In embodiments of thepresent subject matter, an allantoidal shaped braided product 100 a maybe comprised of a section of invariable diameter 101, and a secondsection of invariable diameter 103, in addition to a section oftransitioning diameter 102, in combinations repetitive along thelongitudinal length of the braided product. In embodiments of thepresent subject matter, a plurality of invariable diameter sections maycomprise the allantoidal shaped braided product as well as a pluralityof variable diameter sections, which may or may not be repetitive alongthe longitudinal length of the braided product. In addition, thecross-sectional shape of the allantoidal shaped braided product may becomprised of generally annular shapes including, but not limited tocircular, oval, triangular, square and certain other shapes.

Conventional braided products may be comprised of a two over and twounder (2×2) braid architecture in which two S traveling tow carrierdevices pass under two Z traveling tow carrier devices and then over twoZ traveling tow carrier devices in a repeating pattern. Whenconventional 2×2 braid architectures may be overbraided onto preformswith complex cross-sectional geometry, braided products may stretch insome areas in which the preform may be comprised of largecross-sectional geometry and become compact in areas in which thepreform may be comprised of small cross-sectional geometry. Overbraidingmay be defined as the process in which a braided sleeve structure may beformed over the surface of a preform, generally aligned perpendicularlyto the braiding machine track along the longitudinal axis of thebraiding machine, such that all features comprising the surface of thepreform are covered by the braided sleeve structure and such that thebraided product generally conforms to all features comprising thesurface of the preform. In a non-limiting example of FIG. 1, a 2×2braided product 100 a may stretch across section 101 and become compactacross section 103.

Allantoidal preforms of complex geometry as described herein may becomprised of a liner affixed to a removable core such that the removablecore may provide rigidity to the preform as the braided structure may beoverbraided over the preform of complex geometry, and may be removed toform a commercial braided product comprised of an overbraided liner andbraided structure as described herein.

Areas of large cross-sectional geometry, in which the braided productmay become stretched over the preform, may result in areas of lowcompaction of a braided product while, areas of small cross-sectionalgeometry of a preform, in which a braided structure may become compact,may lead to areas of high compaction of a braided product. Lowcompaction of a braided product may be described as low fiber density inwhich there may be space between tows within the braided structure whilehigh compaction of a braided product may be described as high fiberdensity in which there may be little to no space between tows. Further,in areas of high compaction, tows may overlap with one another or lieatop one another, based on the degree of compaction in high compactionareas of a braided product.

In the case of a 2×2 braided product, compaction may be limited by themaximum distance tow fibers may be stretched apart and limited by howtightly tows may be arranged within the braided structure. Generally,for traditional 2×2 braided products, areas of high and low compaction,or sections of small and large cross-sectional geometry of the preform,may be restricted to a three to one ratio in which the largest sectionof the preform may only be three times larger than that of the smallestsection of the preform. In a continuing example of FIG. 1, the diameterof section 101 may only be three times larger than the diameter ofsection 103. This three to one ratio may limit the variety of productswhich may be created using a 2×2 braided structure.

In addition, bunching or wrinkling may occur when a preform with complexcross-sectional geometry may be overbraided with a 2×2 braidedstructure. This bunching, or wrinkling of the braided structure mayoccur when, in areas of high compaction, tows may become so tightlycompacted that tows may no longer be forced together any further. Stresswithin the braided product may result in the buckling of the braidedstructure to allow for additional compaction in this area to take place.

The high compaction braided product of the present subject matter mayallow for greater variation in the cross-sectional geometry of braidedpreforms as well as the elimination of bunching or wrinkling of abraided structure in areas of complex geometry of the preform.

As described in embodiments herein, the high compaction braided productof the present subject matter may be comprised of 10×10 braidarchitecture. The 10×10 braid architecture of an embodiment maysignificantly increase the difference between the distance tows may bestretched apart and compacted when compared to 2×2 braid architectures.A comparison of the compaction of tows in 10×10 braid architectures and2×2 braid architectures may be illustrated in FIGS. 2, 3 and 4.

FIGS. 2, 3 and 4 are illustrative of varying compaction levels of abraid shown along a cross section, including low compaction 201,intermediate compaction 301 and high compaction 401 of 10×10 braidarchitecture as well as low compaction 202, intermediate compaction 302and high compaction 402 of 2×2 braid architecture. Subsequently, thereis significant difference in compaction between the lowest and highestdegrees of compaction of a 10×10 braid architecture may be achieved whencompared to a standard 2×2 braid architecture. This may allow for the10×10 braid architecture of an embodiment herein to conform to preformsof more complex and variable geometry than may be achieved with 2×2braid architectures.

The 10×10 braid architecture of an embodiment of the present subjectmatter may have particular utility for the creation of high compactionbraided structures with complex and widely variable geometries. Thebraiding machine to produce the 10×10 braid architecture is comprised ofa plurality of tow carrier devices and is significantly larger than thatof a braiding machine of a 2×2 braid architecture comprised of the samenumber of tow carrier devices.

Traditional tow carrier components which support the transfer of towcarriers, also called horn disks, in standard 2×2 braiding machines maybe comprised of four radial slots to accept an average of two total Straveling tow carrier devices as well as an average of two total Ztraveling tow carrier devices to form a 2×2 braid architecture. However,for the creation of a 10×10 braid architecture of an embodiment herein,the horn disks may be comprised of 20 radial slots to accept ten Straveling tow carrier devices as well as ten Z traveling tow carrierdevices. Subsequently, in another embodiment of the present subjectmatter comprising a 5×5 braid architecture, a horn disk may be comprisedof 10 radial slots to accept an average of 5 total S traveling towcarrier devices and an average of 5 total Z traveling tow carrierdevices. Consequently, a horn disk comprised of 20 radial slots for theformation of a 10×10 braid architecture may be 5 times larger than thatof a standard horn disk to accept 20 tow carrier devices in total,significantly increasing the diameter of the braiding machine of thepresent subject matter.

In addition to the increased size of horn disks for 10×10 braidarchitectures in embodiments herein, specialized tow carrier devices maybe created to reduce the effect of “sawing” as tow carrier devicestravel around the braiding machine track of an embodiment of the presentsubject matter. Sawing may be described as an event in which tow lengthand tension change as a result of radial movement of tow carrier devicesaway from and closer to the center of a braiding machine as a result ofthe intertwining of tow carrier devices. In addition, sawing may resultin material being paid off, or pulled off, the tow carrier device as aresult of the varying position of the tow carrier device. Ideally,material may only pay off a tow carrier device as the longitudinallength of the finished braided product increases and as the braidedproduct is pulled from the center of the braiding machine and onto atake-up device.

Sawing may result in an increase in length and tension in a tow as a towcarrier device moves to the outermost radial point from the center ofthe braiding machine on the braiding machine track and may result in thedecrease in tow length and tension as a tow carrier device may move tothe innermost radial point of the braiding machine track to the centerof the braiding machine.

This sawing effect may become exacerbated by the increased size of thehorn disks required for a 10×10 braid architecture of embodimentsherein. To reduce the effects of sawing in a 10×10 braiding machine,specialized tow carrier devices may be created which account for theincreased size of the horn disks in embodiments of the present subjectmatter.

Regarding FIG. 5, typical tow carrier devices 500 a dispersed around abraiding machine 500 may be comprised of a stem 502 on which a spool 513may be affixed, three eyes (middle 505, top 504 and bottom 507) or othertow guide elements including, but not limited to rollers in embodimentsherein, and a method for tensioning the tow 503 as it is paid off thetow carrier device 500 a.

A tow 503, wound on a spool 513, may be passed through the middle 505,bottom 507 and top 504 eyes of a tow carrier device 500 a. The bottomeye 507 of a tow carrier device 500 a may be affixed to a fixture 506which may be allowed to move freely along the longitudinal axis of thetow carrier device 500 a. The fixture 506 to which the bottom eye 507may be affixed in an embodiment, may herein be referred to as the dropweight 506. The longitudinal position of the drop weight 506 and bottomeye 507 assembly may be affected by the position of the tow carrierdevice 500 a within the braiding machine track.

In addition, the drop weight 506 and bottom eye 507 assembly maycomprise a tensioning method for a tow 503 passing through the middle505, bottom 507 and top 504 eyes. In an embodiment of the presentsubject matter, one or a plurality of springs 511 may provide tension tothe tow 503 by providing resistance as the drop weight 506 and bottomeye 507 assembly may travel longitudinally upwards and downwardsthroughout the movement of the tow carrier device 500 a around thebraiding machine track.

Not only may the drop weight 506 and bottom eye 507 assembly comprise amethod for tensioning the tow in a tow carrier device 500 a, the dropweight 506 and bottom eye 507 also may function to control the changinglength of the tow 503 as the tow carrier device 500 a travels around thebraiding machine track.

The movement and longitudinal position of the drop weight 506 and bottomeye 507 assembly may be dictated by the position of the tow carrierdevice 500 a within the braiding machine track in an embodiment of thepresent subject matter.

In an event in which a tow carrier device 500 a may reach the innermostradial point 500 d from the center of the braiding machine, the dropweight 506 and bottom eye 507 assembly may be in the lowest longitudinalposition allowed by the tow carrier device 500 a. At this location, thelength of the tow 503 between the center 500 e of the braiding machine500 and the top eye 504 of the tow carrier device 500 a may be theshortest required during the braiding process. To account for the lengthof the tow at the innermost radial point 500 d, the drop weight 506 andbottom eye 507 assembly may be located at the lowest longitudinalposition allowed by the tow carrier device 500 a. This position mayincrease the length of the tow in the track defined by the middle 505,bottom 507 and top 504 eyes and decrease the length of the tow 503between the top eye 504 and the center 500 e of the braiding machine500.

Subsequently, in an event in which a tow carrier device 500 b may reachthe outermost radial point 500 c from the center 500 e of the braidingmachine 500, the drop weight 506 and bottom eye 507 assembly may be atthe highest longitudinal position allowed by the tow carrier device 500b. At this location, the tow length may be required to be the longestbetween the top eye 504 of the tow carrier device 500 b and the center500 e of the braiding machine 500. To allow the tow 503 to obtain thislength, the drop weight 506 and bottom eye 507 assembly may movelongitudinally upwards to increase the length of the tow 503 between thetop eye 504 and the center 500 e of the braiding machine 500. Thisposition decreases the length of the tow 503 in the track defined by themiddle 505, bottom 507 and top 504 eyes and increases the length of thetow 503 between the top eye 504 and the center 500 e of the braidingmachine 500.

Consequently, the distance of longitudinal travel allowed by a towcarrier device must be equal or greater than half the distance betweenthe innermost and outermost radial points on a braiding machine track tomaintain tension on a tow and to avoid tow material being paid off bythe movement of the tow carrier device around the braiding machinetrack.

If the longitudinal travel distance of the drop weight and bottom eyeassembly were less than half the distance between the innermost andoutermost points on the braiding machine track, when a tow carrierdevice may reach the innermost point on the braiding machine track, thelength of tow between the top eye and the braiding machine center may betoo long, and at the outermost point on the braiding machine track, thetow may be too short. This may result in an undesired length and tensiondifferences.

Additional embodiments of the specialized tow carrier devices of thepresent subject matter illustrated in FIG. 6 may comprise a plurality ofdrop weight 506 and bottom eye 507 assemblies as well as a plurality ofmiddle eyes 505 such that, in a non-limiting example illustrated in FIG.6 of a tow carrier device 600, a tow 503 may pass through a primarymiddle eye and into the bottom eye of a primary drop weight and bottomeye assembly, into a secondary middle eye and a secondary bottom eye ofa secondary drop weight and bottom eye assembly and finally into a topeye 504 of the tow carrier device 600.

The plurality of drop weight 506 and bottom eye 507 assemblies andplurality of middle eyes 505 of the present subject matter may allow forthe same longitudinal travel distance as described in embodiments of thetow carrier devices of the present subject matter, but may allow for atow carrier device 600 of a reduced height such that the totallongitudinal travel distance required in embodiments of the presentsubject matter may be divided between a plurality of drop weight 506 andbottom eye 507 assemblies such that the summation of the longitudinaltravel of each of a plurality of longitudinal travel distances for aplurality of drop weight 506 and bottom eye 507 assemblies may be equalto or greater than half the distance between the inner most and outermost points on a braiding machine track.

FIGS. 7A and 7B summarize the braiding machine process 700 for themovement of the tow carrier devices and the drop weight and bottom eyeassemblies of an embodiment of the present subject matter, includingsteps 714 through 724 from the beginning to the end of the braidingprocess 700. The braiding process begins in step 714. The tow carriertransfer devices, or horn disks, may pass tow carrier devices betweenthem in step 715. In steps 716-723 the position of tow carrier devicesaround the braiding machine track may affect the longitudinal positionof the drop weight and bottom eye assemblies. Steps 716-723 may berepeated until the desired longitudinal length of the braided productmay be obtained. The braiding process may be terminated in step 724.

The high compaction braided structure described herein, of a 10×10 braidarchitecture may have particular utility for the creation of braidedproducts with complex geometry including, but not limited to,allantoidal shaped braided products.

The high compaction braided structure of an embodiment herein may beemployed in the creation of an allantoidal shaped braided structureoverbraided onto a preform. The preform of this embodiment, illustratedin FIG. 9, may be comprised of three distinct sections as defined inFIG. 1, in which there may be two sections of invariable cross-sectionalgeometry, 101 and 103, and in which one section 101 may have a largercross-sectional geometry than the other section 103 of invariablecross-sectional geometry. Additionally, embodiments of FIGS. 1 and FIG.9 may also comprise a section 102 of transitional cross-sectionalgeometry located between the two invariable cross-sectional geometrysections, 101 and 103. FIG. 8 is an example of the braiding machineprocess 800 shown in FIG. 9 and is further described below.

As illustrated in FIG. 9, an embodiment of the high compaction braidedstructure may be overbraided onto the allantoidal shaped preformdescribed herein. In this embodiment, the high compaction braidedproduct may be first overbraided over section 101 of the preform whichmay comprise the largest cross-sectional geometry of the preform. Oversection 101 of largest cross-sectional geometry of the preform, the towsof the braided structure may be arranged side by side with or withoutspace between them in a low compaction arrangement 901.

Consequently, following the overbraiding of section 101, thetransitional section 102 may be overbraided with the high compactionbraided product. As section 102 may be overbraided, the tows of the highcompaction braided structure may become arranged in such a way that thecompaction of the tows increases as the cross-sectional diameter ofsection 102 decreases, resulting in a section of intermediate, ortransitioning compaction 902. In this manner, the braid may conform tosection 102 of varying cross-sectional geometry without bunching orwrinkling the braided structure.

Subsequently, after section 102 may be overbraided, section 103 ofinvariable cross-sectional geometry, smaller than that of section 101,may be overbraided. To account for the difference in cross-sectionaldiameter between section 101 and 103, the tows within the braidedstructure may form an area of high compaction 903 of tows in which towsmay become arranged over top one another and in which there may belittle to no space between tows.

A method illustrating the steps required for overbraiding a preform ofcomplex geometry with a high compaction braided structure, inembodiments herein, may be depicted in FIG. 8. The braiding process 800may begin in step 801 and a preform may be begun to be overbraided instep 802. As the preform may be overbraided in step 802, the highcompaction braided structure may conform to the preform through therearrangement of tows within the braided structure in step 803. In step804, the preform may be completely overbraided and the braiding processmay end in step 805. Additionally, in embodiments, a succession ofpreforms may be overbraided before the braiding process ends in step805.

The high compaction braided structure of the present subject matter maybe one example of a braided structure which may allow for the creationof allantoidal shaped braided products which may also have particularutility for the creation of composite parts which must be readilyexpanded and contracted along the longitudinal axis of the braidedstructure as well as in the radial and bias directions of the braidedstructure.

With regard to FIGS. 10 and 11, in further embodiments of the presentsubject matter, the high compaction braided structure herein maycomprise braided structures including, but not limited to, bellows,those of flabelliform shapes and certain other shapes.

The high compaction braided structure may be overbraided onto a preformlike that illustrated in FIG. 10. In this embodiment, the highcompaction braided structure may allow for the expansion 1000 b andcompression 1000 a of the bellow-like structure through therearrangement of compacted tows within the braided structure while stillmaintaining conformity of the braided structure to the preform.Additionally, the high compaction braided structure described herein maybe comprised of a preform like that illustrated in FIG. 11 of aflabelliform shape which may also be expanded 1100 a and contracted 1100b through the rearrangement of tows within the high compaction braidedstructure.

The high compaction braided structure of embodiments herein may haveparticular utility for braided structures which are desired to undergophysical change as a function of use requirements including, expansionjoints, safety shields, ducting and certain other applications.

The high compaction braided structures of embodiments herein may be oneexample of a braided structure for the creation of allantoidal braidedstructure. An additional example of a braided structure for the creationof allantoidal braided structures comprises a braided structurecomprised of longitudinally varying braid architecture.

In an additional embodiment of a braided structure for the creation ofallantoidal braided structures as well as braided structures withcomplex geometry, the braiding machine and tow carrier devices ofembodiments of the high compaction braided structure described hereinmay comprise a braiding machine for the creation of a braided structurewith longitudinally varying architecture.

As described herein, conventional 2×2 braided structures overbraidedonto preforms of complex geometry, including allantoidal preforms, inwhich the ratio of the largest cross-sectional diameter of the preformmay exceed three times that of the smallest cross-sectional diameter ofthe preform, may stretch in locations of large cross-sectional geometryof the preform and become loose in locations of small cross-sectionalgeometry of the preform. In areas of large cross-sectional geometry ofthe preform, in which the braided structure may be stretched ordistorted, high tension and high bias angles, compared to the nominal,may be induced. Similarly, in areas of small cross-sectional geometry ofthe preform, in which the braided structure may become loose, lowtension and low bias angles may be induced. Further, the braidedstructure may become wrinkled or bunched due to low tension in areas ofsmall cross-sectional geometry and may not conform to the complexgeometry of the preform in areas of small cross-sectional geometry. Inembodiments of the present subject matter, it is desired to eliminatethese distortions in tension and bias angle and to create braidedstructures comprised of uniform tension and bias angle along thelongitudinal length of preforms of complex geometry.

The braided structure comprised of longitudinally varying architectureof embodiments herein, like the high compaction braided structure, mayallow for the formation of braided structures which may be overbraidedonto preforms in which the ratio between the largest cross-sectionaldiameter of the preform to the smallest cross sectional diameter of thepreform may be 3 to 1, 5 to 1, 9 to 1 or 10 to 1 in non-limitingexamples of the present subject matter.

Allantoidal preforms as illustrated in FIG. 1, discussed herein, mayhave commercial use as storage tanks and may be comprised of three mainsections of variable cross-sectional diameter. Sections 101 of theallantoidal preform of FIG. 1 may comprise a tank while section 103 maycomprise a connector. The tanks of the allantoidal preforms may beadapted to endure pressure and the connector may be adapted for use as aflexible gas pressure tube. Each of the tanks may have a first diametercomprising section 101 and each connector may have a second diametercomprising section 103. Section 102 of the allantoidal preform may bedescribed as a transitional portion of the tank located between eachtank and each connector comprising the allantoidal preform. Allantoidalpreforms may be comprised of a plurality of sections 101, 102 and 103resulting in the formation of a multi-tank and flexible connectorstructure which may comprise at least a first tank and a second tank, acylindrical connector located in between the first and the second tankand a two transitional portions with the first located in between thefirst tank and the connection and the second located in between theconnector and the section tank.

In additional examples of allantoidal preforms which may comprise afirst tank and second tank and which may additionally comprise acylindrical connector in between each tank, section 101 may comprise afirst portion while a second portion may comprise a first section 102,section 103 and a second section 102. Additionally, in this example, athird portion may comprise an additional section 101. In furtherexamples of the present subject matter, the second portion may compriseonly section 103.

An embodiment of a braided structure comprised of longitudinally varyingarchitecture may be comprised of a 5×5 starting point braid architecturein which five S traveling tow carrier devices may pass under five Ztraveling tow carrier devices and over five Z traveling tow carrierdevices in a repeating pattern. The braiding machine of an embodiment ofthe present subject matter may be comprised of enlarged horn disks asdescribed in embodiments of the high compaction braided structurediscussed herein. In addition, specialized tow carrier devices may alsobe employed to reduce the affects of sawing as described in anembodiment of the high compaction braided structure for the creation ofallantoidal braided products as well as other braided products ofcomplex geometry.

Additional embodiments of the braiding machine described herein for thecreation of a braided structure with longitudinally varying braidarchitecture may allow for alterations within the braid architecturealong the longitudinal axis during the braiding process to eliminatechanges in tension and bias angle due to distortions within the braidstructure, over the surface of the preform. Further, alterations ofbraid architecture along the longitudinal axis of the braided structuremay be achieved while maintaining the tow materials comprising thebraided structure as contiguous.

Conventional braided structures may generally be comprised of singularbraid architectures along the longitudinal axis of the braided product.To alter the braid architecture of a conventional braided structurealong the longitudinal axis of the braided product, a plurality ofindividual portions of braided products comprising the desired braidarchitectures must be spliced, sewn, or otherwise affixed to one anotherto achieve a braided product with longitudinally varying braidarchitecture. In these cases, tow materials may not be contiguous withinthe transitory braid architecture of the braided product, resulting insections of distorted bias angle, disruption in the braided structureand disruption in the coverage of the braided structure at transitionpoints in which the braid architecture may be altered from one braidarchitecture to another. Coverage of the braided structure may bedefined as fiber density or compaction of tow materials within thebraided structure.

The braided structure with longitudinally varying braid architecture ofthe present subject matter may comprise transitory braid architecturealong the longitudinal axis of the braided structure in which there maybe a seamless transition between braid architectures in which the towmaterials are maintained as contiguous. Maintenance of the tows ascontiguous along the longitudinal axis within the braided structure ofthe present subject matter may be achieved through the removal, orsequester, of tow carrier devices during specific intervals during thebraiding process. Further, alterations within the braid architecture ofthe braided structure of embodiments herein may allow for transitions inthe diameter of the braided product. In a non-limiting example of thepresent subject matter, a 5×5 braid architecture may comprise a largerbraid diameter, a larger plurality of tow carrier devices and mayconform best to larger cross-sectional diameters of a preform of complexgeometry, than small cross-sectional diameters of a preform of complexgeometry. The removal, or sequester, of a plurality of tow carrierdevices from the 5×5 braiding machine of the present subject matter mayresult in the formation of a 1×1 braid architecture comprising a fewernumber of tow carrier devices and which may conform best to small areasof cross-sectional geometry, as opposed to larger areas ofcross-sectional geometry.

In a non-limiting example, an embodiment of the braiding machine of thepresent subject matter may comprise 120 tow carrier devices for themanufacture of a 5×5 braided structure. During the manufacturingprocess, ⅕ of these tow carrier devices may be removed, or sequestered,resulting in the creation of a 4×4 braid architecture comprised of 96remaining tow carrier devices. Subsequently, ¼ of the remaining towcarrier devices may be removed, or sequestered, resulting in thecreation of a 3×3 braid architecture comprised of 72 remaining towcarrier devices. Consequently, the removal of tow carrier devices maycontinue until 24 tow carrier devices remain and a 1×1 braidarchitecture is achieved. Accordingly, each instance in which towcarrier devices may be sequestered may result in a decrease in the braiddiameter of the braided structure of longitudinally varyingarchitecture. Further, the transition in braid architecture, anddiameter, along the longitudinal length of the braided product may allowfor the same bias angle, tension and braid coverage along the length ofthe braided structure to be maintained as no distortion within thebraided structure may occur. Therefore, it may be understood inembodiments of the present subject matter that a large braidarchitecture may correspond with large diameters of the braidedstructure and a small braid architecture may correspond with smalldiameters of the braided structure.

Additionally, the transitory braid architecture of the braided structuredescribed herein may allow for greater ratios of the largestcross-sectional diameter of the preform to the smallest cross-sectionaldiameter of the preform to be overbraided without distortion within thebraided structure, than the three to one ratio for conventional braidedstructures. Therefore, a greater variety of preforms with complexgeometry may be overbraided than may be achieved with conventionalbraided structures. For example, in an embodiment of the present subjectmatter in which the braid architecture may be altered from a 5×5 to a1×1 braid architecture, a preform comprised of a ratio of the largestcross-sectional diameter of the perform to the smallest cross-sectionaldiameter of the preform of at least five to one ratio may be overbraidedwithout distortion in the braided structure.

As described herein, the braided structure comprised of longitudinallyvarying braid architecture of embodiments herein may allow for thecreation of a braided structure comprising constant bias angle, constanttension, the maintenance of tow materials comprising the braidedstructure as contiguous between transitions in braid architecture,maintaining tows as contiguous along the longitudinal axis of the braidand the overbraiding of more complex and widely variable preforms ofcomplex geometry. Further, the braided structure described herein mayadditionally allow for a uniform braid coverage to be achieved along thelongitudinal length of the braided structure. While the high compactionbraided structure of embodiments herein required a transitory braidcoverage, or compaction of tows within the braided structure, to overbraid preforms of complex geometry without distortion, the braidedstructure with longitudinally varying braid architecture of embodimentsherein may maintain a uniform braid coverage along the longitudinallength of the preform to achieve the overbraiding of preforms of complexgeometry though alterations within the braid architecture of the braidedstructure.

FIGS. 12-17 are examples of the braiding machine generally describedregarding the braided structures of FIGS. 18-26 and are furtherdescribed below.

The braided structure with longitudinally varying architecture of thepresent subject matter is illustrated in FIG. 18. As previouslydescribed herein and illustrated in FIG. 1, section 101 of theallantoidal preform may be overbraided with a 5×5 starting point braidarchitecture 1801. After the desired longitudinal length of the braidedstructure of 5×5 braid architecture 1801 may be formed, section 102 ofthe allantoidal preform may be overbraided. Section 102 of theallantoidal preform may be divided into a plurality of distinct sectionsof transitory braid architecture including, a 4×4 braid architecture1802, a 3×3 braid architecture 1803 and a 2×2 braid architecture 1804section which may be equal or unequal in longitudinal length. Followingthe overbraiding of section 102, section 101 of the preform may beoverbraided with a 1×1 end point braid architecture 1805 to obtain thebraided structure with longitudinally varying architecture.

Section 1801 of FIG. 18 may comprise a 5×5 braid architecture. Withinthe 5×5 braid architecture of section 1801 a single S traveling tow 1806may pass over 5 Z traveling tows 1807 and under 5 Z traveling tows 1807in a repeating pattern. Further, a single Z traveling tow 1807 may passunder 5 S traveling tows 1806 and over 5 S traveling tows 1806 in arepeating pattern. As described herein, this repeating pattern may beachieved through the movement of tow carrier devices along a braidingmachine track circumferentially as well as radially inwards and outwardsfrom the center of the braiding machine. A brief discussion of asimplification of the braiding machine as illustrated in FIG. 15 followsto provide reference for the movement of tow carrier devices around abraiding machine track for the formation of the braided structure of thepresent subject matter. A continued discussion of FIG. 18 follows thatof FIG. 15.

A simplification of the braiding machine of an embodiment of the presentsubject matter may be illustrated in FIG. 15. A braiding machine may becomprised of a plurality of nodes 1502, 1504, 1505 and 1512, equallydispersed around a braiding machine track, or ring 1501. Tracks traveledby S and Z tow carrier devices may intersect, forming source nodes 1504and sink nodes 1505. A single node may be a source for one or more S andZ tracks and a sink node for one or more S and Z tracks. A source node1504 may be described as an event in which a tow carrier device maytravel around the outermost track of a braiding machine, farthest fromthe braiding machine center and a sink node 1505 may be described as anevent in which a tow carrier device travels along the innermost track ofthe braiding machine, closest to the braiding machine center.

A typical 2×2 braiding machine comprised of 120 tow carrier devices maygenerally be comprised of 60 nodes with an S and Z track intersectingeach node. For a first set of two nodes, 1505 and 1502, there may be anS edge 1507 in the S direction and a Z edge 1508 in the Z direction.Between nodes 1505 and 1504, S and Z edges may interchange in such amanner that an S edge 1510 may occur on the inner surface of the braidedstructure and a Z edge 1503 may occur on the outer surface of thebraided structure. Between nodes 1505 and 1502, the S edge 1507 mayoccur on the outer surface of the braided structure and the Z edge 1508may occur on the inner surface of the braided structure.

A continued discussion of FIG. 18 with reference to FIG. 15 follows. Asingle S traveling tow carrier device affixed with a spool of towmaterial may be transferred along inner 1510 and outer 1507 S edges of abraiding machine track. As a single S traveling tow carrier device maytravel along an outer S edge 1507 of a braiding machine track, five Ztraveling tow carrier devices affixed with spools of tow materials maytravel along an inner Z edge 1508 of the braiding machine track. The Stow carrier device on the outer S edge 1507 may pay out tow material inthe bias direction as it passes over the five Z traveling tow carrierdevices traveling on an inner Z edge 1508, resulting in the creation ofa portion of the tow material 1806 affixed to the spool on the Straveling tow carrier device on the outer surface of the braidedstructure. Further, this may result in a portion of the tow material1816 affixed to the spools of the Z traveling tow carrier devices on theinner surface of the braided structure. Conversely, as a single Ztraveling tow carrier device may travel along an outer Z edge 1503 of abraiding machine track, five S traveling tow carrier devices affixedwith spools of tow materials may travel along an inner S edge 1510 ofthe braiding machine track. The Z tow carrier device on the outer Z edge1503 may pay out tow material as it passes over the five S traveling towcarrier devices traveling on an inner S edge 1510, resulting in thecreation of a portion of the tow material 1807 affixed to the spool ofthe Z traveling tow carrier device on the outer surface of the braidedstructure. This may further result in a portion of the tow material 1817affixed to the spools of the S traveling tow carrier devices on theinner surface of the braided structure. The pattern of exchange ofportions of tow materials on the inner and outer surfaces of the braidedstructure, or the intertwining of tow materials in a five over fiveunder pattern may result in the formation of a 5×5 braid architecture1801.

The bias angle 1829 of the braided structure of FIG. 18 may be definedby the angle between any S traveling tow 1806, 1808, 1810, 1812 and 1814and the longitudinal axis 1828 of the braided structure or the angle1830 between any Z traveling tow 1807, 1809, 1811, 1813 and 1815 and thelongitudinal axis 1828 of the braided structure wherein the anglebetween any Z traveling tow and the longitudinal axis may be a positiveangle and the angle between any S traveling tow and the longitudinalaxis may be a negative angle.

As described herein, the 5×5 braid architecture 1801 of the presentsubject matter may be overbraided over section 101 of the preform ofcomplex geometry without distortion in the braided structure includingchanges in bias angle, tension and braid coverage. However, inadditional embodiments of the present subject matter, the bias angle1829 and 1830 of the 5×5 braided structures may be transitory along thelongitudinal axis 1828 of section 101 of the preform of complexgeometry. A braided structure comprised of transitory braid architectureas well as transitory bias angle along section 101 of the allantoidalpreform of embodiments of the present subject matter is illustrated inFIG. 18A and is discussed below.

The 5×5 braid architecture 1801 of FIG. 18A may be divided into aplurality of sections 1801 a, 1801 b and 1801 c in embodiments of thepresent subject matter, each with a different bias angle 1825, 1826,1827, 1831, 1832 and 1833 with respect to the longitudinal axis 1828 ofthe braided product. The bias angles of FIG. 18A may be divided into twodifferent groups of positive, 1831, 1832 and 1833, and negative, 1825,1826 and 1827 angles. Section 1801 a may comprise the lowest bias angles1825 and 1831 along the longitudinal length of the braided productdefined by the angle 1825 between any S traveling tow 1806 a and thelongitudinal axis 1828 of the braided structure or the angle 1828between any Z traveling tow 1807 a and the longitudinal axis 1828 of thebraided product. Subsequently, section 1801 b of the 5×5 braidarchitecture may comprise an intermediate bias angle which maytransition the bias angle from section 1801 a to section 1801 c. Thebias angle of section 1801 b may be defined by the angle 1826 betweenany S traveling tow 1806 b and the longitudinal axis 1828 of the braidedproduct and the angle 1832 between any Z traveling tow 1807 b and thelongitudinal axis 1828 of the braided structure. Section 1801 c maycomprise a final section of a plurality of sections of transitory biasangles within the 5×5 braid architecture 1801. The bias angle of section1801 c may be continued throughout sections 102 and 103 of the braidedstructure, through the transitions in braid architecture from 5×5 1801,to 4×4 1802, to 3×3 1803, to 2×2 1804 and finally 1×1 1805. Further, thebias angle of the braided structure may not be altered until anothersection 101 of large cross-sectional diameter of the preform may beoverbraided with a 5×5 braid architecture 1801. In additionalembodiments of the present subject matter, the bias angle of the braidedstructure with longitudinally varying braid architecture may only bealtered along sections of the preform with uniform cross-sectionaldiameter. The bias angle of section 1801 c may be defined by the angle1827 between any S traveling tow 1806 c and the longitudinal axis 1828of the braided structure or the angle 1833 between any Z traveling tow1807 c and the longitudinal axis 1828 of the braided structure. WhileFIG. 18A illustrates a braided structure with longitudinally varyingbraid architecture as well as an increasing transitory bias angle alongsection 101 of the overbraided preform, it may be understood by oneskilled in the art that the bias angle may be decreased along thelongitudinal axis of the braided structure in embodiments of the presentsubject matter. The braided structure of an embodiment of the presentsubject matter overbraided with only a 5×5 braid architecture comprisedof a singular bias angle 1801 is illustrated in FIG. 19 while, anembodiment of the present subject matter comprised of transitory biasangle within the 5×5 braid architecture 1801 overbraided onto anallantoidal preform is illustrated in FIG. 19A.

A discussion of FIG. 18 resumes. Subsequent to the overbraiding ofsection 101 of 5×5 braid architecture 1801 section 102 of the preform ofcomplex geometry may be overbraided. As described herein, section 102may comprise a transitory braid architecture which may transition thestarting point braid architecture, a 5×5 braid architecture 1801 inembodiments of the present subject matter, to an end point architecture,a 1×1 braid architecture 1805 in embodiments of the present subjectmatter. In an embodiment of the present subject matter in which thestarting point braid architecture may be a 5×5 braid architecture, thefirst transition in braid architecture to achieve the 1×1 end pointbraid architecture 1805, of embodiments of the present subject matter,may be from a 5×5 braid architecture to a 4×4 braid architecture 1802.This transition in braid architecture of the present subject matter maybe achieved through the sequestration of tow carrier devices from thebraiding machine track. The sequester of tow carrier devices, asdescribed herein may result in a decrease in the diameter of the braidedstructure as well as a decrease in the braid architecture of the braidedstructure.

A discussion of FIG. 24 which illustrates the removal of tow materialsfrom the braided structure of longitudinally varying braid architecturefor the formation of the braided structure of FIG. 18 is as follows. Inan embodiment of the present subject matter illustrated in FIG. 24 a 4×4braid architecture 1802 may be achieved through the sequester of towcarrier devices from the braiding machine track. The sequester of towcarrier devices from the braiding machine track may result in thetransference of the tow materials affixed to spools operatively affixedto sequestered tow carrier devices from bias tows traveling around thebraiding machine track to axial tows paying out material along thelongitudinal axis of the braided structure on the outer or the innersurface of the braided structure. In an embodiment of the presentsubject matter illustrated in FIG. 24 the sequestered tows may pay outaxial tow material along the longitudinal axis 1828 of the braidedstructure on the inner surface of the braided structure.

In a further example of the present subject matter, tow carrier devicesmay be sequestered from a main braiding machine track to a secondary, ora plurality of secondary braiding machine tracks concentrically arrangedin relation to the main braiding machine track, wherein the towsoperatively affixed to the tow carrier devices may not be converted frombias tows, to axial tows. In this example, sequestered tow carrierdevices may intertwine with one another to form a second layer ofbraided structure on the interior or exterior surface of the braidedstructure formed by the main braiding machine ring and may therefore bemaintained as bias tows.

While FIG. 24 is illustrative of the removal of tow carrier devices fromthe braided structure of the present subject matter comprised of alongitudinally varying architecture, in embodiments of the presentsubject matter, gaps illustrated in the braided structure of FIG. 24 maynot be present, as illustrated in FIGS. 18 and 18A.

Upon the transition in braid architecture from a 5×5 braid architecture1801 to a 4×4 braid architecture 1802, a plurality of tow carrierdevices may be sequestered. As illustrated in FIG. 24, upon thesequester of a plurality of S and Z tow carrier devices, the pluralityof tow materials 2401 and 2402 affixed to the sequestered tow carrierdevices may transition from bias S 1808 and Z 1809 traveling tows to S2402 and Z 2401 axial tows paying out on the inner surface of thebraided structure. While sequestered, tow materials paying out materialalong the longitudinal axis of the braided structure 1828 may notinteract with the braided structure. The transference of tow materialsfrom bias tows to axial tows may reduce the quantity of tow carrierdevices in the braiding machine track and therefore may result in analteration in the braid architecture of the braided structure from a 5×5braid architecture 1801 to a 4×4 braid architecture 1802.

A 4×4 braid architecture 1802 may generally be comprised of a repeatingpattern in which four S traveling tow carrier devices may pass over fourZ traveling tow carrier devices and under four Z traveling tow carrierdevices and in which four Z traveling tow carrier devices may pass underfour S traveling tow carrier devices and over four S traveling towcarrier devices. With regard to FIGS. 15, 18 and 24, within a 4×4 braidarchitecture, a single S traveling tow carrier device traveling on anouter S edge 1507 may pass over four Z traveling tow carrier devicestraveling on inner Z edges 1508. As the single S traveling tow carrierdevice may pass over four Z traveling tow carrier devices, a portion ofS tow material 1808 may be formed on the outer surface of the braidedstructure while potions 1819 of the Z traveling tows may be formed onthe inner surface of the braided structure. Additionally, a single Ztraveling tow carrier device traveling on an outer Z edge may pass overfour S traveling tow carrier devices traveling on inner S edges 1510. Asthe single Z traveling tow carrier device may pass over the four Straveling tow carrier devices, a portion of Z tow material 1809 may beformed on the outer surface of the braided structure while portions 1818of the S traveling tows may be formed on the inner surface of thebraided structure. The intertwining of tow materials and the exchange oftow carrier devices from inner and outer edges of the braiding machinetrack may result in the formation of a 4×4 braid architecture 1802.Further, the bias angles 1829 and 1830, of the 4×4 braid architecture ofsection 1802 may comprise the angle between any S traveling tow 1808 andthe longitudinal axis 1828 of the braided structure 1828 or any Ztraveling tow 1809 and the longitudinal axis 1828 of the braidedstructure. While the 4×4 braid architecture of the present subjectmatter may be braided, axial tows 2401 and 2402 may continue to pay outmaterial along the longitudinal axis of the braided structure on theinner surface of the braided structure. The braided structure of thepresent subject matter overbraided with both a 5×5 1801 and 4×4 1802braid architecture is illustrated in FIG. 20.

Following the overbraiding of a first portion of section 102, in acontinued discussion of FIGS. 15, 18 and 24, the braid architecture mayagain be decreased from a 4×4 braid architecture 1802 to a 3×3 braidarchitecture 1803 to continue to transition the 5×5 starting point braidarchitecture 1801 to the 1×1 end point braid architecture 1805. Thealteration in braid architecture from the 4×4 braid architecture 1802 tothe 3×3 braid architecture 1803, like the transition in braidarchitecture from a 5×5 braid architecture 1801 to a 4×4 braidarchitecture 1802 may be achieved through the sequestration of towcarrier devices. Additionally, the bias angle of the braided structuremay be maintained from the 4×4 braid architecture 1802 to the 3×3 braidarchitecture 1803. The bias angle of the 3×3 braid architecture 1803region of section 102 may be defined as the angles 1829 and 1830,between any S traveling tow 1810 and the longitudinal axis 1828 of thebraided structure or the angle between any Z traveling tow 1811 and thelongitudinal axis 1828 of the braided structure.

A 3×3 braid architecture may be achieved through the transference of aplurality of S and Z traveling tows 2403 and 2404 from bias tows toaxial tows within the braided structure. At the transition from the 4×4braid architecture 1802 to the 3×3 braid architecture 1803 a pluralityof S 2404 and Z 2403 tows operatively affixed to spools affixed to towcarrier devices may be sequestered and may transition from bias tows toaxial tows, resulting in a decrease of tow materials within the braidingmachine track and therefore altering the braid architecture of thebraided structure from a 4×4 braid architecture to a 3×3 braidarchitecture. Further, the diameter of the braided product may again bereduced to conform to the preform of complex geometry and to maintainbias angle and tension within the braided structure.

A 3×3 braid architecture may be comprised of a repeating pattern inwhich three S traveling tow carrier devices may pass over three Ztraveling tow carrier devices and under three Z traveling tow carrierdevices and in which three Z traveling tow carrier devices may passunder three S traveling tow carrier devices and over three S travelingtow carrier devices in a repeating pattern. A 3×3 braid architecture1803 may be formed in a manner such that a single S traveling towcarrier device affixed with a spool of tow material may travel along anouter S edge 1507 and pass over three Z traveling tow carrier devicestraveling on an inner Z edge 1508. As the S traveling tow carrier devicemay pass over three Z traveling tow carrier devices, a portion of S towmaterial 1810 may be formed on the outer surface of the braidedstructure while portions of Z traveling tow material 1821 may be formedon the inner surface of the braided structure. Further, a single Ztraveling tow carrier device may travel along an outer Z edge 1503 andmay pass over three S traveling tow carrier devices traveling on aninner S edge 1510. Additionally, as the Z tow carrier device may passover three S traveling tow carrier devices a portion of Z tow material1811 may be formed on the outer surface of the braided structure whileportions of the S traveling tows 1820 may be formed on the inner surfaceof the braided structure. The intertwining of S and Z tow materials maycontinue to form a 3×3 braid architecture 1803. During the formation ofthe 3×3 braid architecture 1803 axial tows 2401, 2402, 2403 and 2404 maycontinue to pay out material along the longitudinal axis 1828 of thebraided structure. The braided structure of the present subject mattercomprising a 5×5 1801, a 4×4 1802 and a 3×3 1803 braid architecture isillustrated in FIG. 21.

Following the braiding of a predetermined longitudinal length of 3×3braid architecture 1803, in a continuing discussion of FIGS. 15, 18 and24, the braid architecture may again be altered in an additional step tocontinue to transition the starting point braid architecture, a 5×5braid architecture 1801, to a 1×1 end point braid architecture 1805. Inthis step, the braid architecture may be altered from a 3×3 braidarchitecture 1803 to a 2×2 braid architecture 1804. Like the transitionsbetween previous braid architectures comprising the braided structure,the transition in braid architecture in this step of the braidingprocess may be achieved through the sequester of tow carrier devices andthe transference of bias tow materials to axial tow materials, reducingthe quantity of tow carrier devices in the braiding machine track andresulting in a decrease in braid diameter. The bias angles, 1829 and1830, comprising the 3×3 braid architecture 1803 may be maintainedwithin the 2×2 braid architecture 1804 and may be defined as the anglebetween any S traveling tow 1812 and the longitudinal axis 1828 of thebraided structure or the angle between any Z traveling tow 1813 and thelongitudinal axis of the braided structure 1828. During the formation ofthe 2×2 braid architecture all sequestered tow materials may continue topay out material axially along the longitudinal axis of the braidedstructure along the inner surface of the braided structure.

A 2×2 braid architecture may be comprised of a repeating pattern inwhich two S traveling tow carrier devices may pass over two Z travelingtow carrier devices and under two Z traveling tow carrier devices and inwhich two Z traveling tow carrier devices may pass under two S travelingtow carrier devices and over two S traveling tow carrier devices in arepeating pattern. A 2×2 braid architecture may be formed such that asingle S traveling tow carrier device traveling on an outer S edge 1507may pass over two Z traveling tow carrier devices traveling on an innerZ edge 1508 resulting in the formation of a portion 1812 of S towmaterial forming on the outer surface of the braided structure and theformation of portions 1823 of Z tow material on the inner surface of thebraided structure. Further, a single Z traveling tow carrier devicetraveling on an outer Z edge 1503 may pass over two S traveling towcarrier devices traveling on inner S edges 1510 resulting in theformation of portions 1813 of Z tow material formed on the outer surfaceof the braided structure and portions of S tow material 1822 formed onthe inner surface of the braided structure. The intertwining of towmaterials in this manner may result in the formation of a 2×2 braidarchitecture 1804. FIG. 22 illustrates an allantoidal preformoverbraided with 5×5 1801, 4×4 1802, 3×3 1803 and 2×2 1804 braidarchitectures along the longitudinal axis 1828 of the braided structure.

Following the overbraiding of the preform of complex geometry with thedesired longitudinal length of 2×2 braid architecture 1804, in acontinued discussion of FIGS. 15, 18 and 24, the final transition inbraid architecture to achieve the 1×1 end point braid architecture ofembodiments of the present subject matter may occur. This transition maybe achieved through the sequester of a final plurality of tow carrierdevices from the braiding machine track, resulting in a final quantityof tow carrier devices comprised within the braiding machine track whichmay interact to form a 1×1 brad architecture 1805, a decrease in thediameter of the braided product, and the transition of a plurality ofbias tow materials to axial tow materials. Upon the transition in braidarchitecture from a 2×2 braid architecture 1804 to a 1×1 braidarchitecture 1805 all tows sequestered during the formation of thebraided structure with longitudinally varying braid architecture maycontinue to pay out material axially along the longitudinal axis of thebraided structure. However, subsequent to the final sequestration of towcarrier devices from the braiding machine track and during the formationof the 1×1 end point braid architecture, all axial tow materials may behelically wrapped around section 103 of the preform as described herein.The helical wrapping of tow materials around section 103 of theallantoidal preform of embodiments of the present subject matter isillustrated in FIG. 24.

The helical wrapping of tow materials around section 103 of FIG. 1 asillustrated in FIG. 24 allows for section 103 of the allantoidal preformto be flexed into a variety of different angular positions. FIG. 23A isadditionally illustrative of the helical wrapping of tows around section103 illustrated in FIG. 1 of the allantoidal preform. As illustrated inFIG. 23A, a single tow may be removed from a plurality of intertwiningbias tows at a removal point 2301 on the cross-section of the braidedstructure. Subsequently, the removed tow may be reintroduced back intothe braided structure at a reintroduction point 2302 on thecross-section of the braided structure and may intertwine again with thebias tows. A tow which is removed at a removal point 2301 from theplurality of intertwining bias tows may be helically wrapped around thesurface of the preform and reintroduced to the braided structure at areintroduction point 2302. As a result of the helical wrapping of theremoved tow, the reintroduction point 2302 may be located at an angulardisplacement from the removal point 2301, as depicted in FIG. 23B, andmay further be displaced along the longitudinal axis of the braidedstructure. In additional embodiments of the present subject matter, thereintroduction point 2302 may be located at the same angle as theremoval point 2301 but may still be displaced along the longitudinalaxis of the braided structure. FIG. 23B is illustrative of a crosssection of the braided structure and preform and depicts the angulardisplacement of the removal 2301 and reintroduction 2302 points.Additionally, the removed tow may be spirally wrapped at a positive ornegative angle, which may be envisioned as a third bias angle, withrespect to the longitudinal axis of the braided structure.

As previously discussed in the specification herein allantoidal preformsmay be comprised of a plurality of tanks for the creation of amulti-tank and flexible connector structure, flexible connectors andtransitional portions in repetitive patterns along the longitudinalaxis; wherein an allantoidal preform comprised of at least two tanks maycomprise a series of a first tank, a second tank, a connector located inbetween the first and second tank and two transitional portions suchthat the first transitional portion may be located between the firsttank and the connector and the second may be located between theconnector and the second tank. The helical wrapping of sequestered towmaterials allows for flexibility within the braided structure such thatthe connector may have a radius of curvature and that the tankscomprising the allantoidal preforms may be arranged non-collinearly. Thenon-collinear arrangement of allantoidal preforms is illustrated in FIG.26 which will be discussed below.

The flexing of section 103 allows for a non-collinear arrangement ofallantoidal preforms of the present subject matter as illustrated inFIG. 26. FIG. 26 is illustrative of a flexed connector 2604 comprising aradius of curvature 2606 in which a first tank 2603 may have a firstlongitudinal axis 2602 and a second tank 2605 may have a secondlongitudinal axis 2601 and the flexed connector 2604 may be repositionedwithin a range of the radius of curvature 2606 such that the first tank2603 and the second tank 2605 are adaptable to be repositioned whereinat least the first tank longitudinal axis 2602 or the second tanklongitudinal axis 2601 is oriented at a plurality of bias directionswith respect to the longitudinal axis 1828.

If the helical wrapping of tows were omitted in this step of thebraiding process, axial tow materials may continue to pay out materialalong the longitudinal axis of the braided structure as illustrated inFIG. 25. As the axial tows, 2401, 2402, 2403 and 2404, may continue toform along the surface of the preform, the longitudinal length of thetows along section 103 of FIG. 1 may be similar. The axial tows ofsimilar length along section 103 may result in a rigid braided structurealong section 103 of the allantoidal preform, in which only a collineararrangement of allantoidal preforms may be achieved.

In a continuing discussion of FIGS. 15, 18 and 24, the 1×1 end pointbraid architecture 1805 of section 103 of the allantoidal preform may becomprised of a repeating pattern such that one S traveling tow carrierdevice may pass over one Z traveling tow carrier device and under one Ztraveling tow carrier device and in which one Z traveling tow carrierdevice may pass under one S traveling tow carrier device and over one Straveling tow carrier device in a repeating pattern. The 1×1 end pointbraid architecture 1805 may be formed such that one S tow carrier devicetraveling on an outer S edge 1507 may pass over one Z tow carrier devicetraveling on an inner Z edge 1508 forming a portion of S traveling towmaterial 1814 on the outer surface of the braided structure and aportion of Z traveling tow material on the inner surface of the braidedstructure. Further, one Z tow carrier device traveling on an outer Zedge 1503 may pass over one S tow carrier device traveling on an inner Sedge 1510 forming a portion of Z tow material 1815 on the outer surfaceof the braided structure and a portion of S tow material on the innersurface of the braided structure. This intertwining of tow materials mayresult in the formation of a 1×1 braid architecture 1805.

Once a 1×1 end point braid architecture may be achieved along section103 of FIG. 1, the braiding process may continue until a juncturecomprising the allantoidal preform between sections 103 and 102 of thepreform, adjacent to a subsequent section 101 of the allantoidalpreform, may be reached. At this juncture illustrated in FIG. 25, it maybe desired to increase the 1×1 braid architecture to a 5×5 braidarchitecture to overbraid sections 102 and 101 of the allantoidalpreform. In this case, the starting point braid architecture, the 1×1braid architecture 1805 may be increased to a 5×5 end point braidarchitecture 1801 through the addition of tow carrier devices into thebraiding machine track resulting in the transference of axial towmaterials into bias tow materials. As the transitory braid architectureof section 102 is overbraided, a plurality of axial tow materials 2401,2402, 2403, 2404 may be introduced back into the braiding machine trackupon each transition in braid architecture such that upon the finaltransition in braid architecture from a 4×4 braid architecture 1802 tothe 5×5 end point braid architecture 1801, all axial tows previouslypaying out tow material along the inner surface of the braided structure2500 may be transitioned to bias tows and all tow materials mayintertwine to from the 5×5 braid architecture 1801 of embodiments of thepresent subject matter. As illustrated in the braided structure 2500 ofFIG. 25, upon the transition in braid architecture from a 3×3 braidarchitecture 1803 to a 4×4 braid architecture 1802, axial tows 2403 and2404 may be transitioned into bias tows in which axial tow 2403 maybecome an S traveling bias tow and axial tow 2404 may become a Ztraveling bias tow. Further, illustrated in FIG. 25, axial tow 2401 maybe transitioned into an S bias tow while axial tow 2402 may betransitioned into a Z traveling bias tow.

The braiding process may then repeat such that the starting point braidarchitecture may be a 5×5 braid architecture and the end point braidarchitecture may be a 1×1 braid architecture.

The braiding machine illustrated in FIGS. 12-17 for the formation of thebraided structure of FIGS. 18-26 will be discussed below. The braidingmachine, illustrated in FIG. 12, of embodiments herein for the creationof a braided structure with longitudinally varying architecture may beaffixed with a method of sequestering tow carrier devices from thestandard braiding machine track, or the outer braiding machine track1203, to transition tow materials from bias tows to axial tows. Further,the outer braiding machine track 1203 may be affixed with a method toalter the standard outer braiding machine track 1203 to allow for thecreation of a plurality of sequestering or acquisition tow carrierdevice tracks which may enable transfer of tow carrier devices from theouter braiding machine track 1203 to tow carrier sequestering devicesaffixed to a sequester ring 1212. Tow carrier sequestering devices mayfacilitate the removal of tow carrier devices to achieve the transitorybraid architecture of embodiments of the present subject matter throughthe conversion of tow materials between bias and axial tows whilemaintaining the tow materials as contiguous.

In additional examples herein, the tow materials operatively affixed tosequestered tow carrier devices may be maintained as bias tows whereinin place of a sequester ring 1212, the braiding machine of examplesherein may comprise an additional braiding machine ring such that towcarrier devices may be removed from the outer braiding machine track1203 to an inner braiding machine track, or a braiding machine trackcircumferentially arranged within or outside of the outer braidingmachine track 1203. In this example during the braiding process, anadditional layer of braid may be formed on the interior or exteriorsurface of the braided structure formed by the outer braiding machinetrack 1203.

The formation of an allantoidal braided structure comprised oflongitudinally varying braid architecture, illustrated in FIG. 18, whichmay transition between starting and ending braid point architectures of5×5 1801 and 1×1 1805 braid architectures may be created with a braidingmachine, of which several components are illustrated in FIG. 13,comprised of 24 enlarged horn disks 1304 as described herein as well as120 specialized tow carrier devices which may reduce the effects ofsawing. The braiding machine of the present subject matter may be viewedin FIGS. 12, 13, 14, 15, 16 and 17. The braiding machine, partiallyillustrated in FIGS. 12 and 13 and the cross-section of which isillustrated in FIG. 14, of the present subject matter may further becomprised of an outer braiding machine ring 1213, an sequester ring1212, sequester tracks 1214, horn disks 1304, switcher pucks 1209,sequester disks 1305, an outer braiding machine track 1203, a pluralityof S traveling tow carrier devices and a plurality of Z traveling towcarrier devices.

With regard to FIG. 12, sequester tracks 1214 of the present subjectmatter may begin with equal curvature to a sequester branch of the outerbraiding machine track 1203, and may end with equal curvature to anacquisition branch of the outer braiding machine track 1203. Theacquisition and sequester branches of the present subject matter may betangent to the outer braiding machine track 1203 on one end and tangentto the sequester tracks 1214 on the other end, and may further may beaffixed to the outer braiding machine track 1203 of the outer braidingmachine ring 1213.

The formation of the allantoidal braided structure comprised oflongitudinally varying braid architecture may begin with theoverbraiding of section 101 of FIG. 1 with a 5×5 starting point braidarchitecture 1801, illustrated in FIG. 18. This 5×5 braid architecture1801 may be formed by the braiding machine, with regard to FIGS. 16 and17, described herein comprised of 120 tow carrier devices, 1601 and1602, dispersed along the outer braiding machine ring 1213 and which maybe guided by the outer braiding machine track 1203. As the 5×5 braidarchitecture 1801 may be braided along section 101 of FIG. 1 of theallantoidal preform of the present subject matter, switcher pucks 1209may be rotated into a braiding position in which the curvature of theouter braiding machine track 1203 may be complete and in which towcarrier devices, 1601 and 1602, may not be transferred out of the outerbraiding machine ring 1213 or interact with sequester and acquisitionbranches of the outer braiding machine track 1203. The rotation of theswitcher pucks 1209 into a braiding position may be illustrated in FIG.17. Subsequently, as tow carrier devices, 1601 and 1602, pass switcherpuck 1209 locations there may be no interaction between sequester tracks1214 and the tow carrier devices, 1601 and 1602. The 5×5 braidarchitecture 1801 of the braided structure described herein overbraidedonto an allantoidal preform is illustrated in FIG. 19.

The switcher pucks 1209 of the present subject matter, illustrated inFIGS. 16 and 17, may be affixed to the outer braiding machine ring 1213and may be comprised of a plurality of partial braiding machine tracks,or switcher tracks 1205, which may interact with the sequester andacquisition branches of the outer braiding machine track 1203 as well assequester tracks 1214 of the sequester ring 1212. In embodiments hereineach switcher puck 1209 may be comprised of two switcher tracks 1205, amain switcher track and an alternative switcher track. A switcher puck1209 rotated into a braiding position may complete the curvature of theouter braiding machine track 1203 through the interaction of the mainswitcher track with the outer braiding machine track 1203. Subsequently,a switcher puck 1209 rotated into a braiding position may not allow forthe transfer of tow carrier devices, 1601 and 1602, into or out of theouter braiding machine track 1203.

Additionally, in a continued discussion of FIGS. 16 and 17, a switcherpuck 1209 may be rotated into a switch position in which tow carrierdevices, 1601, and 1602, may be transferred into or out of the outerbraiding machine track 1203. A switcher puck 1209 in a switch positionmay complete sequestering or acquisition tow carrier device pathscomprising acquisition or sequester branches of the outer braidingmachine track 1203, alternative switcher tracks and sequester tracks1214. Therefore, a switcher puck 1209 in the switch position may allowfor the transfer of tow carrier devices, 1601 and 1602, into or out ofthe outer braiding machine track 1203.

Switcher pucks 1209 of embodiments of the present subject matter may berotated in specific groups in such a manner that S and Z tow carrierdevices, 1601 and 1602, may be sequestered or introduced back into andout of the outer braiding machine ring 1203 at different intervals.Therefore, S and Z tow carrier devices, 1601 and 1602, may betransferred into and out of the outer braiding machine track 1203separately from one another.

The transfer of S and Z tow carrier devices in specific groups may beaccomplished through the interaction of gears which may rise and fall,affixed beneath horn disks or sequester disks, to interact withstationary gears affixed beneath horn disks or sequester disks such thathalf the rise and fall gears may be engaged with half the stationarygears at a time to allow transfer of a plurality of S or Z tow carrierdevices between the rings comprising the braiding machine of the presentsubject matter. Additionally, flippers, clutches or certain othercomponents may be utilized to transfer the tow carrier devices in groupsof S or Z tow carrier devices.

Additionally, sequester disks 1305 to accept a plurality of tow carrierdevices, 1601 and 1602, may accept only S or Z tow carrier devices, 1601and 1602, during each sequestration cycle. Further, sequester disks1305, like the switcher pucks 1209 may be actuated in specific groupssuch that upon sequestration of S tow carrier devices 1601, half thesequester disks 1305 may rotate for the acceptance of S tow carrierdevices 1601 while the remaining half of the sequester disks 1305 mayremain stationary.

Once the desired longitudinal length of the 5×5 braided structure of thepresent subject matter along section 101 of FIG. 1 of the allantoidalpreform may be achieved, and the braided structure may be formed alongthe preform until the transition between 101 and 102 may be reached,illustrated in FIG. 19, the braiding process may be interrupted and ⅕ ofthe tow carrier devices, 1601 and 1602 illustrated in FIGS. 16 and 17,may be transitioned from the outer braiding machine ring 1213 to thesequester ring 1212 where the tow carrier devices, 1601 and 1602, may besequestered within the sequester disks 1305.

The removal of tow carrier devices, 1601 and 1602 of FIGS. 16 and 17,may be facilitated by a plurality of switcher pucks 1209 rotated intothe switch position, in which a S sequestering tow carrier path may becreated to allow the transfer of S tow carrier devices 1601 from theouter braiding machine ring 1213 into the sequester ring 1212. Switcherpucks 1209 rotated in a switch position may be illustrated in FIG. 16.

A tow carrier device, 1601 and 1602, removed from the standard braidingmachine track 1203 by a switcher puck 1209 may be sequestered within asequester track 1214 comprising a sequester ring 1212 and may be heldwithin a sequester track 1214 until it is desired to re-introduce thesequestered tow carrier device, 1601 and 1602, back into the outerbraiding machine track 1203. Generally, each time a plurality of towcarrier devices, 1601 and 1602, may be sequestered from the outerbraiding machine track 1203 the sequester disks 1305 may rotate to allowfor an additional plurality of tow carrier devices, 1601 and 1602, to beremoved until the sequester disks 1305 may be filled and a 1×1 braidarchitecture 1805, of FIG. 18, may be achieved.

After the rotation of a plurality of switcher pucks 1209, illustrated inFIGS. 17 and 17, the braiding process may begin until a plurality of Stow carrier devices 1601 may be transitioned from the outer braidingmachine track 1203 into alternative switcher tracks comprising switcherpucks 1209 and into sequester tracks 1214 surrounding each sequesterdisk 1305. In embodiments herein, after the transfer of the S towcarrier devices 1601 from sequester branches of the outer braidingmachine ring 1203 as described, the switcher pucks 1209 may be rotatedsuch that the main switcher track of the switcher pucks 1209 mayinteract with the outer braiding machine track 1203 and such that thealternative switcher track may no longer complete an S sequestering towcarrier device track. Once a tow carrier device, 1601 and 1602, hasentered into a sequester track 1214, each sequester disk 1305 may berotated into position to accept another tow carrier device, 1601 and1602. Following the sequester of the plurality of S tow carrier devices1601, a plurality of Z tow carrier devices 1602 may be sequestered inthe same manner; a plurality of switcher pucks 1209 may be rotated intothe switch position for the formation of Z sequestering tow carrierdevice tracks, the plurality of Z tow carrier devices 1602 may betransferred to sequester tracks 1214 and the plurality of switcher pucks1209 may be rotated into the braiding position. Subsequent to thesequester of the S and Z tow carrier devices, 1601 and 1602, a total of⅕^(th) of the initial 120 tow carrier devices, 1601 and 1602, ofembodiments of the braiding machine herein may be sequestered insequester disks 1305. In an embodiment of the present subject matter,the braiding process may begin again with 96 tow carrier devices, 1601and 1602, dispersed around the outer braiding machine track 1203 andwith 24 tow carrier devices, 1601 and 1602, sequestered in the sequesterdisks 1305 affixed to the sequester ring 1212. In additional embodimentsof the present subject matter, one or more additional S or Z tow carrierdevices, 1601 and 1602, may be transferred into sequester disks 1305before the rotation of the switcher pucks 1209 and the resumption of thebraiding process.

Upon the sequester of ⅕ of the tow carrier devices from the outerbraiding machine ring 1213 to the sequester ring 1212, tow materialsaffixed to spools operatively affixed to sequestered tow carrier devicesmay be transitioned from bias tows, intertwining for the formation ofthe braided structure of the present subject matter, to axial tows,which do not interact with the braided structure and which may pay outtow material along the longitudinal axis 1828, illustrated in FIG. 18,of the braided structure along the inner surface of the braidedstructure.

In a continuing discussion of FIGS. 16 and 17, the sequester disks 1305of embodiments of the present subject matter may allow for theacceptance of a pre-determined quantity of tow carrier devices, 1601 and1602, from the outer braiding machine track 1203 into radial slotscomprising the sequester disks 1305. This pre-determined quantity may bechosen based on the number of transitions between starting and endingbraid point architectures for the formation of the braided structurewith longitudinally varying architecture. In non-limiting examples ofthe present subject matter, the transition from a 6×6 starting pointbraid architecture to a 1×1 end point braid architecture may require theremoval of 5 sets of tow carrier devices to achieve the transition, andtherefore the sequester disks 1305 of the embodiment must be able toaccept at least 5 tow carrier devices, 1601 and 1602, and therefore mustcomprise at least 5 radial slots.

Within a braiding machine, comprised of 120 tow carrier devices, for theformation of a 5×5 braid architecture, two S tow carrier devices 1601may be dispersed on one S edge and three S tow carrier devices 1601 onthe adjacent edge in a repeating pattern. Similarly, there may be threeZ tow carrier devices 1602 on the opposing Z edge and two Z tow carrierdevices 1602 on the adjacent Z edge in a repeating pattern.

Upon the removal of ⅕ of the tow carrier devices as described herein, totransition from section 101 to section 102 of FIG. 1 of the allantoidalpreform of embodiments herein, a 4×4 braid architecture 1802,illustrated in FIG. 18, may be achieved in which there may be two S towcarrier devices 1601, dispersed around the outer braiding machine track1203 of FIGS. 16 and 17, remaining on one S edge and two S tow carrierdevices 1601 remaining on an adjacent edge in a repeating pattern whilethere may be two Z tow carrier devices 1602 remaining on the opposing Zedge and two Z tow carrier devices 1602 remaining on the adjacent Z edgein a repeating pattern.

Upon the removal of ⅕^(th) of the tow carrier devices from the outerbraiding machine track 1203, 96 tow carrier devices, 1601 and 1602, ofthe initial 120 tow carrier devices, 1601 and 1602, may remain dispersedalong the outer braiding machine track 1203. After the plurality ofswitcher pucks 1209 have been rotated into the braiding position suchthat the outer braiding machine track 1203 is completed by the mainswitcher track of the switcher pucks 1209, the braiding process maybegin for the formation of a 4×4 braid architecture 1802, of FIG. 18.

At a predetermined longitudinal length along section 102, illustrated inFIG. 20, the braiding process may be halted and ¼th of the remaining towcarrier devices, 1601 and 1602 of FIGS. 16 and 17, may be removed,altering the repeating pattern of S and Z tow carrier devices, 1601 and1602, to one S tow carrier device 1601 on one S edge and two S towcarrier devices 1601 on the adjacent S edge, two Z tow carrier devices1602 on the opposing Z edge and one Z tow carrier device 1602 on theadjacent Z edge. The removal of ¼^(th) of the remaining tow carrierdevices may occur in the same manner as the removal of ⅕^(th) of theoriginal 120 tow carrier devices, 1601 and 1602.

Consequently, at the point which it is desired to remove ¼^(th) of the96 remaining tow carrier devices, 1601 and 1602, from the outer braidingmachine track 1203, a plurality of switcher pucks 1209 may be rotatedinto the switch position such that the alternative switcher track of theswitcher pucks 1209 may form a S sequestering tow carrier device trackthrough which S tow carrier devices 1601 may travel and to allow for Stow carrier devices 1601 to be removed from the outer braiding machinetrack 1203 and into the sequester tracks 1214. After a plurality of Stow carrier devices 1601 may be transferred into sequester tracks 1214,the sequester disks 1305 may be rotated to accept a plurality ofadditional tow carrier devices, 1601 and 1602. Accordingly, the switcherpucks 1209 may be rotated into the braiding position such that the mainswitcher track of the switcher pucks 1209 may complete the outerbraiding machine track 1203 and tow carrier devices, 1601 and 1602, mayno longer be transferred from the outer braiding machine track 1203 tosequester tracks 1214. This same process may be repeated for thesequestration of a plurality of Z tow carrier devices 1602. As a resultof the sequestration of S and Z tow carrier devices, 1601 and 1602,¼^(th) of the remaining tow carrier devices, 1601 and 1602, may beremoved from the outer braiding machine ring 1213. Subsequently,braiding may begin with 72 remaining tow carrier devices, 1601 and 1602,dispersed around the outer braiding machine track 1203 and with 48 towcarrier devices, 1601 and 1602, sequestered in the sequester tracks 1214surrounding the sequester disks 1305 within the sequester ring 1212resulting in a 3×3 braid architecture 1803.

Upon the sequester of ¼ of the tow carrier devices from the outerbraiding machine ring 1213 to the sequester ring 1212, tow materialsaffixed to spools operatively affixed to sequestered tow carrier devicesmay be transitioned from bias tows, intertwining for the formation ofthe braided structure of the present subject matter, to axial tows,which do not interact with the braided structure and which may pay outtow material along the longitudinal axis of the braided structure alongthe inner surface of the braided structure.

Successively, at an additional point defined by the longitudinal lengthof the braided product comprised of a 3×3 braid architecture 1803illustrated in FIG. 21, the braiding process may again be halted and aplurality of switcher pucks 1209, of FIGS. 16 and 17, may be rotatedinto the switch position to result in the creation of an S sequesteringtow carrier path and to allow the removal of a plurality of theremaining S tow carrier devices 1601 from the outer braiding machinetrack 1203. A plurality of S tow carrier devices 1601 may then betransitioned from the outer braiding machine track 1203 to sequestertracks 1214 as described herein. The sequester disks 1305 may then berotated, in embodiments of the present subject matter to accept aplurality of additional tow carrier devices, 1601 and 1602.Additionally, the plurality of switcher pucks 1209 may be rotated suchthat the outer braiding machine track 1203 may be completed by the mainswitcher track of the switcher pucks 1209. The process may then berepeated for a plurality of Z tow carrier devices 1602. Subsequent tothe removal of ⅓^(rd) of the remaining tow carrier devices, 1601 and1602, from the outer braiding machine track 1203, 48 tow carrierdevices, 1601 and 1602, may remain dispersed along the outer braidingmachine track 1203 while 72 tow carrier devices, 1601 and 1602, may besequestered in sequester tracks 1214 affixed to the sequester ring 1212.This arrangement of tow carrier devices, 1601 and 1602, of embodimentsherein may result in the formation of a 2×2 braid architecture 1804,illustrated in FIG. 18.

In a continuing discussion of FIGS. 16 and 17, The removal of ⅓^(rd) ofthe remaining tow carrier devices, 1601 and 1602, may alter the patternof S and Z tow carrier devices, 1601 and 1602, in the outer braidingmachine track 1203 to one S tow carrier device 1601 on one S edge andone S tow carrier device 1601 on the adjacent S edge, one Z tow carrierdevice 1602 on the opposing Z edge and one Z tow carrier device 1602 onthe adjacent Z edge. Further, the sequester of ⅓^(rd) of the remainingtow carrier devices from the outer braiding machine ring 1213 to thesequester ring 1212 may result in the conversion of tow materialsaffixed to sequestered tow carrier devices from bias tows to axial tows,which may pay out material along the longitudinal axis of the braidedstructure.

Consequently, after the desired longitudinal length of the braidedstructure with a 2×2 braid architecture 1804 may be braided, illustratedin FIG. 22, and the transition between section 102 and 103 of FIG. 1 maybe reached ½ of the remaining tow carrier devices, 1601 and 1602 ofFIGS. 16 and 17, may be removed from the outer braiding machine track1203.

At the transition between section 102 and 103 of the allantoidal preformof embodiments herein, illustrated in FIG. 1, ½ of the remaining towcarrier devices, 1601 and 1602 of FIGS. 16 and 17, may be transitionedfrom the outer braiding machine track 1203 and into sequester tracks1214 surrounding each of the sequester disks 1305. The tow carrierdevices, 1601 and 1602, may be removed in the same manner as describedin previous steps of the braiding process herein. Upon the removal of ½of the remaining tow carrier devices, 1601 and 1602, from the outerbraiding machine track 1203, 24 tow carrier devices, 1601 and 1602, mayremain dispersed along the outer braiding machine track 1203 while 96tow carrier devices, 1601 and 1602, may remain sequestered within thesequester ring 1212.

The removal of ½ of the remaining tow carrier devices, 1601 and 1602,may alter the pattern of S and Z tow carrier devices, 1601 and 1602, inthe outer braiding machine track 1203 to one S tow carrier device 1601on one S edge and no S tow carrier devices 1601 on the adjacent S edge,no Z tow carrier devices 1602 on the opposing Z edge and one Z towcarrier device 1602 on the adjacent Z edge. Additionally, the sequesterof ½ of the remaining tow carrier devices may result in the transferenceof tow materials affixed to the sequestered tow carrier devices frombias tows to axial tows.

After the removal of ½ of the remaining tow carrier devices, inembodiments herein, the sequester ring 1212 comprising the sequesterdisks 1305 and the sequestered tow carrier devices, 1601 and 1602, maybe rotated as described in embodiments of the present subject matter. Aspreviously discussed in an embodiment herein, this rotation may allowfor flexibility within the braided structure. The omission of rotationin this step or any other step of embodiments herein may result in theformation of a ridged braided structure. In embodiments of the presentsubject matter, rotation of the sequester ring 1212 may occur at anypoint during the braiding process including upon the sequester of towcarrier devices, 1601 and 1602, from the outer braiding machine track1203, between any transition in braid architecture or any other intervalduring the braiding process.

Further, the degree to which the sequester ring may be rotated maydetermine the degree of flexibility within the braided structure of thepresent subject matter. In a non-limiting example, if the sequester ringwere to be rotated a single sequester disk position, very littleflexibility may be created within the braided structure, however, if thesequester ring were to be rotated one full revolution, much moreflexibility may be allowed within the braided structure.

Subsequent to the braiding of the desired longitudinal length of braidedstructure of a 1×1 braid architecture 1805, illustrated in FIG. 18,along section 103 of FIG. 1, and when the transition between section 103and 102 of the allantoidal preform may reached, the braid architectureof the braided structure may again be altered to increase the braidarchitecture from a 1×1 starting point braid architecture 1805 to a 2×2braid architecture 1804 to conform to the variable cross-sectionalgeometry of section 102 and to begin the transition from the 1×1starting point braid architecture 1805 to a 5×5 end point braidarchitecture 1801.

The transition in braid architecture between a 1×1 braid architecture1805, of FIG. 18, and a 2×2 braid architecture 1804 may occur in asimilar manner to the removal of the tow carrier devices, 1601 and 1602of FIGS. 16 and 17, as described herein. To transition the braidarchitecture of the braided structure of embodiments herein from a 1×1braid architecture 1805 to a 2×2 braid architecture 1804, the braidingprocess may be halted and a plurality of sequester disks 1305 may berotated to transfer a plurality of S tow carrier devices 1601 fromsequester disks 1305 to horn disks 1304. After the transfer of theplurality of S tow carrier devices 1601 from sequester disks 1305 tohorn disks 1304, the S tow carrier devices 1601 may still be comprisedwithin sequester tracks 1214. A plurality of switcher pucks 1209 maythen be rotated into the switch position in which the outer braidingmachine track 1203 may be disrupted and the alternative switcher tracksof the switcher pucks 1209, the acquisition branches of the outerbraiding machine ring 1213, and the sequester tracks 1214 may form Sacquisition tow carrier device tracks. After the transfer of S towcarrier devices 1601 back into the outer braiding machine track 1203,the sequester disks 1305 may be rotated such that a plurality of towcarrier devices, 1601 and 1602 may be in position to re-enter the outerbraiding machine track 1203. The plurality of switcher pucks 1209 maythen be rotated into the braiding position in which the outer braidingmachine track 1203 may be completed by the main switcher track of theswitcher pucks 1209. The process may be repeated for a plurality of Ztow carrier devices 1602; a plurality of Z tow carrier devices 1602maybe transferred from sequester disks 1305 to horn disks 1304, aplurality of switcher pucks 1209 may rotate into the switch position toform Z acquisition tow carrier device tracks, the plurality of Z towcarrier devices 1602 may be transferred into the outer braiding machinetrack 1203 and the plurality of switcher pucks 1209 may be rotated intothe braiding position. The introduction of tow carrier devices, 1601 and1602, into the outer braiding machine track 1203 may result in 48 towcarrier devices, 1601 and 1602, dispersed around the outer braidingmachine track 1203 and 72 tow carrier devices, 1601 and 1602,sequestered within the sequester ring 1212. In other embodiments of thepresent subject matter, a plurality of additional tow carrier devices,1601 and 1602, may be introduced back into the outer braiding machinetrack 1203 during the sequestration cycle. In additional embodiments ofthe present subject matter, before the introduction of ¼^(th) of the towcarrier devices, 1601 and 1602, from the sequester ring 1212 into theouter braiding machine track 1203, the sequester ring 1212 comprisingthe sequester disks 1305 and the sequestered tow carrier devices, 1601and 1602, may again be rotated to allow for increased flexibility withinthe braided structure with longitudinally varying architecture.

Upon the transition in braid architecture from a 1×1 to a 2×2 braidarchitecture and the addition of ¼^(th) of the remaining sequestered towcarrier devices, 1601 and 1602 of FIGS. 16 and 17, into the outerbraiding machine track 1203, the pattern of S and Z tow carrier devices,1601 and 1602 may be altered to one S tow carrier device 1601 on one Sedge and one S tow carrier device 1601 on the adjacent S edge, one Z towcarrier device 1602 on the opposing Z edge and one Z tow carrier device1602 on the adjacent Z edge.

After the desired longitudinal length of the braided structure of 2×2braid architecture 1804 may be achieved, the braid architecture maycontinue to be increased from a 2×2 braid architecture 1804, to a 3×3braid architecture 1803, illustrated in FIG. 18 through the same methodas described herein; through the addition of ⅓^(rd) of the tow carrierdevices, 1601 and 1602 illustrated in FIGS. 16 and 17, sequesteredwithin the sequester ring 1212 into the outer braiding machine track1203. The addition of ⅓^(rd) of the sequestered tow carrier devices,1601 and 1602, may result in 72 tow carrier devices dispersed around theouter braiding machine track 1203 and 48 tow carrier devices, 1601 and1602, sequestered within the sequester ring 1212. Additionally, upon thetransition in braid architecture from a 2×2 1804 to a 3×3 braidarchitecture 1803 and the addition of ⅓^(rd) of the remainingsequestered tow carrier devices, 1601 and 1602, into the outer braidingmachine track 1203, the pattern of S and Z tow carrier devices, 1601 and1602 may be altered to one S tow carrier device 1601 on one S edge andtwo S tow carrier devices 1601 on the adjacent S edge, two Z tow carrierdevices 1602 on the opposing Z edge and one Z tow carrier device 1602 onthe adjacent Z edge.

In a continuing discussion of FIGS. 16, 17 and 18, subsequent to thebraiding of the desired longitudinal length of the braided structure of3×3 braid architecture 1803 of the present subject matter, the braidarchitecture of the present subject matter may again be altered from a3×3 braid architecture 1803 to a 4×4 braid architecture 1802 through theaddition of ½ of the remaining sequestered tow carrier devices, 1601 and1602, from the sequester ring 1212 to the outer braiding machine track1203. This may result in 96 tow carrier devices, 1601 and 1602,dispersed around the outer braiding machine track 1203 and 24 towcarrier devices sequestered within the sequester ring 1212. Further,upon the addition of ½ of the remaining sequestered tow carrier devices,1601 and 1602, into the outer braiding machine track 1203, the patternof S and Z tow carrier devices, 1601 and 1602, may be altered to two Stow carrier devices 1601 on one S edge and two S tow carrier devices1601 on the adjacent S edge, two Z tow carrier devices 1602 on theopposing Z edge and two Z tow carrier devices 1602 on the adjacent Zedge.

Consequently, after the desired longitudinal length of 4×4 braidarchitecture 1802 along section 102, of FIG. 1, of the allantoidalpreform may be braided, and the transition from section 102 to 101 maybe reached, the braid architecture may again be altered from a 4×4 braidarchitecture 1802 to a 5×5 braid architecture 1801. This transition inbraid architecture may be achieved through the transfer of all remainingtow carrier devices, 1601 and 1602, from the sequester ring 1212 intothe outer braiding machine track 1203. This transfer of tow carrierdevices, 1601 and 1602, may result in 120 tow carrier devices, 1601 and1602, dispersed around the outer braiding machine track 1203 and noremaining tow carrier devices, 1601 and 1602, present in the sequesterring 1212. Further, upon the addition of the remaining sequestered towcarrier devices, 1601 and 1602, into the outer braiding machine track1203, the pattern of S and Z tow carrier devices, 1601 and 1602, may bealtered to two S tow carrier devices 1601 on one S edge and three S towcarrier devices 1601 on the adjacent S edge, three Z tow carrier devices1602 on the opposing Z edge and two Z tow carrier devices 1602 on theadjacent Z edge.

Throughout each transition in braid architecture from the 1×1 startingpoint braid architecture 1805 to the 5×5 end point braid architecture1801, as described herein, each introduction of tow carrier devices fromthe sequester ring 1212 to the outer braiding machine ring 1213 mayresult in the conversion of axial tows to bias tows. Further, upon thetransition from the 4×4 braid architecture to the 5×5 end point braidarchitecture all tow materials comprising the braiding machine may bebias tows interacting to form the braided structure of the presentsubject matter.

The method for the overbraiding of allantoidal preforms of embodimentsherein may be continued until the desired length of the braidedstructure of the present subject matter may be achieved.

An embodiment of the present subject matter may have particular utilityfor the manufacture of braided structures to be deployed in dry or resinimpregnated form in composite parts comprised of a repeating series ofgenerally allantoidal preforms comprised of generally annular crosssections with each adjacent pair of allantoidal shaped preformsconnected by relatively narrower annular cross sections or conduits asshown in FIG. 1.

While the braided structure with longitudinally varying architecture hasbeen discussed in embodiments herein as overbraided over allantoidalpreforms of complex geometry, in additional embodiments of the presentsubject matter, the braided structure with longitudinally varyingarchitecture may be overbraided onto a plurality of preforms withcomplex geometry of non-allantoidal shape or configuration.

Additional embodiments of the braided structure with longitudinallyvarying architecture may be comprised of different start point and endpoint braid architectures. In a non-limiting example, an additionalembodiment may be comprised of alternating 4×4 and 2×2 regions withcorresponding transition architectures between each start and end pointarchitecture. Further alternate embodiments may be comprised of varyingpatterns of start and end point architectures and the correspondingtransitions. For example, one alternate braid structure may be comprisedof a 5×5 region transitioned to a 3×3 region transitioned to a 5×5region to a 1×1 region and so on in any pattern required by the finaldeployment of the braid structure.

An alternate embodiment of the present subject matter may include towcarrier devices comprised of a plurality of tow materials such that amaterial gradient may be obtained along the braided structure oflongitudinally varying architecture as well as a gradient in braidarchitecture of the braided structure described herein.

Further, in additional embodiments of the present subject matter eachsequestered group of tow carrier devices may be comprised of a pluralityof tow materials such that the removal of one set of tow carrier devicesmay sequester a particular material from the braided structure until itis desired to reintroduce the material at another predeterminedinterval.

An additional embodiment of the present subject matter may be comprisedof a braided structure with longitudinally varying architecture whichmay incorporate a combination of a plurality of tow materials in whichthe ratio of the plurality of tow materials may be dictated by thesequester of specific sets of tow carrier devices at specific intervalsduring the manufacturing process.

In a non-limiting example of the present subject matter, a braidingmachine comprised of 120 tow carrier devices may be comprised of 5 setsof 24 tow carrier devices comprised of different tow materials.Initially during the braiding process, all tow carrier devices may beintermixed resulting in a braided structure comprised of five differenttow materials and comprised of a 5×5 braid architecture. At apredetermined interval, ⅕th of the tow carrier devices may besequestered. This plurality of tow carrier devices or, one of 5 sets of24 tow carrier devices, may be removed from the outer braiding machinering and transferred into the sequester ring. This one set of 24 towcarrier devices may comprise all the tow carrier devices of a specifictow material.

Subsequently, the manufacturing process may begin again for theformation of a braided structure comprised of 4 different sets of towcarrier devices comprised of four different tow materials. At anadditional predetermined interval in the braiding process, ¼th of theremaining tow carrier devices may be sequestered in such a way that the1 set of 24 tow carrier devices may comprise all of the same towmaterial. Upon production of the braided structure, the braidedstructure may be composed of 3 sets of 24 different tow materials.

Consequently, the process may then continue until one specific set oftow materials may remain.

In an additional embodiment of the present subject matter, upon thesequester of tow carrier devices comprising a specific tow material, anadditional set of tow carrier devices comprising a specific tow materialsequestered within the sequester disks may be introduced back into theouter braiding machine track. In this manner, the braid architecture ofthe braided structure may be maintained but the material of which thebraided structure may be comprised may be altered. This process may becontinued with the removal and addition of specific tow materials atintervals in which tow carrier devices may be sequestered. Further, atchosen intervals the braid architecture may be altered and no exchangeof tow carrier devices may take place.

An additional embodiment of the braiding machine of the present subjectmatter may be comprised of 120 tow carrier devices. At the beginning ofthe manufacturing process 96 tow carrier devices of the same ordiffering tow materials may be sequestered within the sequester ringwhile 24 tow carrier devices may be dispersed around the outer braidingmachine ring. The 24 tow carrier devices within the outer braidingmachine ring may be exchanged with ¼ of the tow carrier devices in thesequester ring at different intervals to form a continuous 1×1 braidedstructure with varying sections of tow materials. This method may alsobe used to create a 1×1 braided structure of the same tow material andmay be used to prolong the intervals in which re-doffing of the braidingmachine may occur. This method may also be used to form other braidedstructures with differing architectures including 2×2, 3×3, 4×4, 5×5 andother braid architectures.

An additional embodiment of the present subject matter may allow for thecreation of a braided structure comprised of a constant ratio ofspecific tow materials. In a non-limiting example, an embodiment of abraiding machine may be comprised of 120 tow carrier devices comprisedof 4 sets of different tow materials. Of the 120 tow carrier devices,four sets of 30 tow carrier devices may contain different tow materials.Upon the sequester of 24 tow carrier devices to transition from a 5×5braid architecture to a 4×4 braid architecture the tow carrier devicesmay be sequestered in such a way that 6 of each of the tow carrierdevices of the four different tow materials may be removed. The towcarrier devices may be sequestered in such a fashion that each sequesterof tow carrier devices may maintain the same ratio of tow carrierdevices with different tow materials such that when the 1×1 braidarchitecture may be achieved and 24 tow carrier devices remainun-sequestered, 4 sets of 6 tow carrier devices comprising different towmaterials remain.

Additional embodiments of the present subject matter may comprisebraiding machines of greater pluralities of tow carrier devices to allowfor additional variations of annular cross-sectional sized braidedstructures to be manufactured and a variety of different braidarchitectures to be achieved. For example, a braiding machine comprisedof 144 tow carrier devices may be employed to result in the transitionof braid architecture from a 6×6 braid architecture to a 1×1 braidarchitecture. In opposition, an additional embodiment may be comprisedof fewer tow carrier devices to achieve similar braid architectures withsmaller annular cross-sectional diameters.

An additional embodiment of the present subject matter may comprise abraided structure with longitudinally varying architecture of thepresent subject matter in which the braid architecture of the braidedstructure may be varied in such a manner to create sections of variablecompaction within the braided structure to allow for flexibility ofmovement of the braided structure in some areas while other areas of thebraided structure may be rigid. Additionally, the braid architecture maybe varied in such a manner to create areas of high and low tow densityacross a preform of complex geometry. In a non-limiting example of thepresent subject matter, a braided structure may be comprised of aplurality of braid architectures in specific locations along thelongitudinal length of the preform including a 10×10 braid architectureof embodiments herein as well as a 1×1 braid architecture. Sections ofthe braided structure comprising 10×10 braid architecture may allow forlocations of high tow density as well as expansion and contraction ofthe braided structure. Additionally, sections of 1×1 braid architecturemay comprise locations of low tow density and may not allow forexpansion and contraction of the braided structure.

While embodiments of the braided structure with longitudinally varyingbraid architecture have been discussed herein as comprised of biaxialbraided structures, embodiments of the present subject matter maycomprise triaxial braided structures in which there may be three sets ofintertwining tows for the formation of the braided structure of thepresent subject matter; two sets of tows oriented in the bias directionand one set of tows oriented along the longitudinal axis of the braidedproduct. Embodiments of the braided product described herein comprisedof triaxial braided structures may result in the formation of braidedstructures in which the allantoidal form of the braided structure may belocked in place such that the braided structure may maintain anallantoidal form when removed from the preform of complex geometry asdiscussed herein.

An additional embodiment of the present subject matter may comprise abraided sleeve comprising a plurality of tows, wherein the braidcomprises a longitudinal axis and a first portion, a second portion anda third portion along the longitudinal axis. The first portion maycomprise one or more of the plurality of tows intertwined with one ormore of the other tows of the plurality of tows. The second portion ofthe braid may comprise one of the plurality of tows removed from beingintertwined with a remaining plurality of tows such that the removed towmay be located in one of an interior or exterior of the braided sleeve.Additionally, the third portion of the braid may comprise the removedtow intertwined back with the remaining plurality of tows. Further, thethird portion of the braided sleeve may comprise the reintroduction ofthe removed tow into the braid to be intertwined with the remainingplurality of tows forming the braided sleeve structure.

The braided sleeve may also comprise the second portion wherein thesecond portion comprises a fourth and fifth portion in sequence prior tothe third portion along the longitudinal axis of the braided structure.The fourth portion may comprise an additional one of the plurality oftows and the additional removed tow, located in the exterior or theinterior of the braided sleeve. The fifth portion may comprise theadditional removed tow intertwined with the remaining plurality of tows.

Further, the second portion may comprise two of the plurality of towsremoved from being intertwined with the remaining plurality of tows suchthat the two tows may be located on the interior or the exterior of thebraided sleeve. Additionally, the third portion may comprise one of thetwo of the plurality of tows being intertwined with the remainingplurality of tows and the other of the two of the plurality of towsbeing intertwined on the interior or the exterior of the braided sleeve.

The braided sleeve of additional embodiments of the present subjectmatter may further comprise the braided sleeve comprising asubstantially circular cross-section transverse to the longitudinal axiswherein the removed tow may be removed from the remaining plurality oftows at a removal point on the substantially circular cross-section andmay be intertwined with the remaining plurality of at a reintroductionpoint on the substantially circular cross-section of the braided sleeve.The removed tow may be spirally wrapped on the interior or the exteriorof the braided sleeve in the second portion as described herein whereinthe reintroduction point is at an angular displacement from the removalpoint around the substantially circular cross section. Additionally, theremoved tow may be spirally wrapped such that the reintroduction pointis at the same angle on the substantially circular cross section as theremoval point and the reintroduction point is at a longitudinaldisplacement from the removal point.

The braided sleeve may further comprise the first portion of the braidcomprising the plurality of tows arranged in substantially a pluralityof bias directions with respect to the longitudinal axis wherein theplurality of bias directions includes a first and a second biasdirection, the second portion comprising the remaining plurality of towsintertwined in the first bias direction and the second bias directionand wherein the third portion may comprise the removed tow intertwinedwith the remaining plurality of tows in the first bias direction and thesecond bias direction.

Additionally, the braided sleeve of embodiments herein may furthercomprise the first portion of the braid comprising the plurality of towsintertwined with one or more tows of the other plurality of towsarranged in substantially a plurality of bias directions with respect tothe longitudinal axis wherein the plurality of bias directions have aplurality of angles with respect to the longitudinal axis and whereinthe plurality of bias directions include a first bias direction at apositive angle, a second bias direction at a negative angle, a thirdbias direction at a positive angle and a fourth bias direction at anegative angle. The first bias direction may be different from the thirdbias direction and the second bias direction may be different from thefourth bias direction such that the plurality of tows may be intertwinedin the first and second bias direction. Further, at least one of thesecond portion may comprise the remaining plurality of tows intertwinedin the third bias direction and the fourth bias direction or the thirdportion comprising the removed tow intertwined with the remainingplurality of tows intertwined in the third bias direction and the fourthbias direction.

The braided sleeve may additionally comprise the second portion furthercomprising the removed tow being spirally wrapped in a fifth biasdirection at a positive or negative angle with respect to thelongitudinal axis wherein the fifth bias direction may be different thanthe first and second bias direction.

In an additional embodiment of the present subject matter, the braidedsleeve may comprise a substantially circular cross-section transverse tothe longitudinal axis wherein the second portion may further comprise anadditional one of the plurality of tows removed from being intertwinedwith the remaining plurality of tows wherein the plurality of removedtows includes a first removed tow and a second removed tow and the firstremoved tow may be spirally wrapped on the exterior or the interior ofthe braid in a first bias direction and the second removed tow may bespirally wrapped on the exterior or the interior of the braid in asecond bias direction wherein the first bias direction may be differentfrom the second bias direction.

In an additional embodiment of the present subject matter, the braidedsleeve of embodiments herein may comprise a braid comprising alongitudinal axis and a plurality of tows wherein the plurality of towsmay be contiguous along the longitudinal axis such that at least some ofthe plurality of tows may be intertwined with one or more other tows ofthe plurality of tows and one of the plurality of tows may be removedfrom being intertwined with a remaining plurality of tows along aportion of the longitudinal axis and that the removed tow may beintertwined with the remaining plurality of tows along another portionof the longitudinal axis.

A further embodiment of the braided structure with longitudinallyvarying braid architecture comprises a braid reinforcement for amulti-tank and flexible connector structure comprising a braided sleeveincluding a plurality of tows wherein the braided sleeve comprises alongitudinal axis and such that the braided sleeve is configured to forma plurality of cylindrical tanks and a cylindrical connector along thelongitudinal axis. Each of the tanks may comprise a first diameter andeach connector may comprise a second diameter such that the plurality oftanks including a first tank and a second tank such that the cylindricalconnector may be located in between the first and second tank.Additionally, the first tank may comprise at least some of the pluralityof tows intertwined with one or more other tows of the plurality of towsand the connector may comprise one of the plurality of tows removed frombeing intertwined with a remaining plurality of tows and the removed towbeing located on the exterior or the interior of the braided sleevewherein the second diameter may be smaller than the first diameter andthe second tank may comprise the removed tow being intertwined with theremaining plurality of tows. The braid reinforcement of the presentsubject matter may comprise a ratio of the first diameter to the seconddiameter of approximately 3 to 1, 4 to 1, 5 to 1, 6 to 1, 7 to 1, 8 to1, 9 to 1 or 10 to 1.

The braid reinforcement of embodiments herein may comprise a firsttransitional portion and a second transitional portion along thelongitudinal axis wherein the first transitional portion may be locatedin between the first tank and the connection and the second transitionalportion may be located in between the connector and the second tank. Theconnector may further comprise at least an additional one of theplurality of tows removed from being intertwined with the remainingplurality of tows and may be located in the exterior of the interior ofthe braided sleeve. Additionally, each of the first transitionalportions and the second transitional portions may comprise theadditional one of the plurality of tows which may be intertwined withthe remaining plurality of tows.

The braid reinforcement may further comprise the connector ofembodiments herein comprising a radius of curvature wherein the firsttank may have a first longitudinal axis and the second tank may have asecond longitudinal axis and the connector may be configured to berepositioned within a range of a radius of curvature so that the firsttank and the second tank maybe adaptable to be repositioned wherein atleast one of the first tank longitudinal axis or the second tanklongitudinal axis may be oriented at a plurality of bias directions withrespect to the longitudinal axis.

Further additional embodiments of the present subject matter maycomprise a set of vessels adapted to endure pressure comprising thebraid reinforcement of embodiments herein and may additionally comprisea flexible gas pressure tube within the braided sleeve.

An embodiment of the method for the production of the braided sleeve maycomprise the steps of firstly, forming a braid comprising a plurality oftows, a longitudinal axis and a first portion, a second portion and athird portion along the longitudinal axis. Secondly along the firstportion, intertwining the plurality of tows with one or more other towsof the plurality of tows. Thirdly, along the second portion, removingone of the plurality of tows from being intertwined with a remainingplurality of tows and relocating the removed tow to the interior or theexterior of the braided sleeve and fourthly, along the third portion,intertwining the removed tow with the remaining plurality of tows.

The method for the production of the braided sleeve of embodiment of thebraided structure with longitudinally varying architecture ofembodiments herein may additionally include the steps of along thesecond portion, forming a forth portion and a fifth portion in sequenceprior to the third portion along the longitudinal axis, along the forthportion intertwining an additional one of the plurality of tows removedfrom being intertwined with the remaining plurality of tows andrelocating the additional removed tow to the interior or the exterior ofthe braided sleeve and along the fifth portion, intertwining theadditional removed tow with the remaining plurality of tows.Additionally, the method may comprise the steps of along the secondportion, removing two of the plurality of tows from being intertwinedwith the remaining plurality of tows and relocating the removed two ofthe plurality of tows to the interior or the exterior of the braidedsleeve, and along the third portion intertwining the one of the two ofthe plurality of tows with the remaining plurality of tows andrelocating the other of the two of the plurality of tows on the interioror the exterior of the braided sleeve. Further, the method may comprisethe step of along the second portion, wrapping the removed tow in aspiral around at least one of the interior or the exterior of thebraided sleeve.

While the above subject matter has been illustrated and described indetail in the drawings and foregoing discussion, the same is to beconsidered as illustrative and not restrictive in character, it beingunderstood that example embodiments have been shown and described andthat all changes and modifications that come within the scope and spiritof the invention are embraced by the disclosure.

1-20. (canceled)
 21. A braided sleeve comprising: a braid having alongitudinal axis and including a plurality of tows; the plurality oftows being contiguous along the longitudinal axis; at least some of theplurality of tows being intertwined with one or more other tows of theplurality of tows; a set of the plurality of tows being removed frombeing intertwined with a remaining plurality of tows along a firstportion of the longitudinal axis; and each tow of the set of towsfurther being intertwined with at least one of the other tows of the setof tows along a second portion of the longitudinal axis.
 22. A braidedsleeve comprising: a braid including a plurality of tows, the braidhaving a longitudinal axis and forming a first portion, a second portionand a third portion of the braid along the longitudinal axis; the firstportion comprising the plurality of tows intertwined with each other;the second portion comprising at least one of the plurality of towsremoved from being intertwined with a remaining plurality of tows atleast along a length of the second portion and being located in one ofthe interior or the exterior of the braided sleeve; and the thirdportion comprising the removed tow intertwined with the remainingplurality of tows.